RPN – Droid48  is free. 

Electodroid is a cool free app, btw.  Just handy quick reference stuff

The "annoy-a-tron" from thinkgeek.com.  I left one as a retirement present in the basement of a good friend, near his electronics workbench.  It entertained him for two weeks, before he found it attached to my note of good wishes.  A great design for a frivolous purpose.  An interesting implementation of little events at long random intervals, without the disastrous consequences that happen to our normal devices.

The best one I ever ran across was back in the 70s, when microprocessors were just hitting the market.  While shopping for blenders at the local discount store, I noticed one of the models had a sign that promised "contains microprocessor".  As a person with a pretty good idea of the odds of a $25 microprocessor being embedded in a $12 blender, I had to find out, so my trusty pocket protector provided the needed calibration screwdriver and I set to work to remove the base plate.

When the base was off, there it sat, proudly bearing the Intel logo. Glued to the sidewall was an undoubtedly non-functional microprocessor, having no electrical connections of any sort, but certainly fulfilling the promise of containing a microprocessor.

Funniest embedded application ever…  I designed the "Mount Count" about 5 years ago.  It's an estrus detection system to tell when cows go into heat.  For all of modern technology, the best indicator is when the cow is mounted by the bull. I'm not sure if the bulls are sterilized or not but apparently the ranchers want to know the optimum time to artificially inseminate their cows.
 
The device consisted of a small low-power microcontroller running off a Li battery.  The board was mounted inside a clear plastic case and the assembly gets glued onto the back of the cow just above her tail.  When an 1,800 lb bull mounts her the housing compresses and closes a small micro-switch.  The processor counts the number of mounts over a certain period of time with a surprisingly complex and proprietary algorithm. When the magic happens an LED blinks to tell the rancher the time is right.

Newer systems nowadays use wireless transmitters.

I pursued an EIT and PE right after college, and have maintained it with fees and continuing education. Is it worth it? I think so, for me. My school prepared me well, and the tests were lengthy, but not difficult. Peer review and recommendation also plays a part in the process. I expect many other PE's feel the same way. Most PE's that I have met have been very competent engineers. I have also worked with many very competent engineers without certification. The difference seems to lie with the poor chumps who were promised an engineering education and got a degree, but really did not get their money's worth. They are convinced (by their diploma mill) that they are engineers, but have difficulty with stuff that I learned in freshman year. Unfortunately, I have worked with far too many of them, and they can be dangerous. These folks would not have a chance with the tests, and likely would not get peer recommendations.

So my initial expectations of a PE are higher than the average "engineer", but either has opportunity to earn or lose my respect. Most PEs live up to my expectations.

"Engineer" means different things in different places. In England, it's the guy who wires your house. In the US, it may refer to the guy who drives the train or the bulldozer. In Germany, it is quite limited to someone who is certified and has an advanced college degree. A lot of folks like to argue this point, I really don't care that much.

The proceedings of my state agency included land surveyors, engineers, morticians, barbers, beauticians, and bingo parlors. That is pretty much the inverse order of disciplinary actions. It was interesting to learn about all the screw-ups that happen in the various professions. I learned to cut my own hair.

You know, Argentina may be big in terms of square meters, but is a small country. I'm in charge of R&D at this company (I'm the one and only) and have also been in charge of tech support some years ago, stuff that was handled by a technician. Through the years I've had the honor of getting in touch with excellent professionals, and the sadness of meeting people with absolutely no knowledge of electronics, that questioned the quality of the components this company sales.

My usual response to the internals carrying those people's comments was "tell him to go to one of those houses that have a sign showing "University" in the front, there he'll find what he is looking for". You know, to work as a physician, you need to have credentials from a university certifying you are a doctor. Otherwise, you'll meet a demand for illegal exercising medicine (or something similar, I'm translating legal terms in spanish...). To work as an attorney, same stuff. To work in electronics... well, anyone will do. I'd like to have the legal equivalent of "illegal exercise of engineering" !

There is a certification, it is called university degree. We could start by requiring developers to at least be engineers. As for firmware... well, I don't have credentials to support that, I'm self taught in C, my university program taught me BASIC, Pascal, and I've learned 6800 assembly in high school. Beyond that, my teachers were good enough to provide me with the right tools so I can learn new programming languages and firmware techniques, but that's what we engineers know how to do, that's why we are engineers, isn't it ? Anyway, it is a tough question and our countries and educational systems are quite different, but I'm sure there are lots of stuff that can be done so the engineering degree is enough for a certification as a developer.

"...and would probably leave the industry if this happened, is it inevitable?"

I too would leave engineering if it came to pass.  In fact I'd have no choice but leave because I'm a member of the set of people that lack an engineering degree.

That said I agree that standards should exist for the development of complex embedded systems.  Accreditation seems to be a logical way to address the situation but unfortunately the legal requirement for a PE is going to eliminate a lot of highly qualified people like myself.
We'll be  relegated to non-critical systems or forced to work in jurisdictions without this stricture or forced out of the field completely.  A debate needs to happen about how high code quality can be achieved without alienating qualified outliers.

One of the responsibilities in my position as a 'Firmware Design Supervisor' is to select whom to hire when presented with a pile of resumes.  I try very hard to review them with unprejudiced eyes.  A PE qualification means almost nothing to me.  I always wonder if the HR filter that proceeds me has eliminated someone unconventional like myself.  I'm still thankful for the foot in the door I received 13 years ago when I transitioned from mechanical to software eng (My convoluted path = University Physics degree dropout -> Art School -> Fine Art Lithographer -> Tool and Die Maker -> Mold Maker -> CAD/CAM programmer (auto and aerospace) -> Firmware Designer -> Contract Software Developer (various from open source to legacy systems reverse engineering) -> Widget Inventor -> Present (I am a poorly tuned servo wrt vocation)).  I cannot in good conscience be a gatekeeper for a guild that would refuse to have me as a member.

Isn't that what engineering diploma is?  Licensing doctors and lawyers has more to do with the guild style limit on the number of practitioners than anything else.  The problem is that 'engineering' is not taught in college; only engineering disciplines are.

I would also like to mention that software engineering has its specifics but you really need to start with engineering fundamentals, i.e., problem definition, problem analysis, problem space analysis (not only possible solutions but also what adjacent areas will be affected).  These subjects are taught but they are not practiced as 'hacking' is cool and can produce results quickly but engineering is boring because it involves a lot of non-coding things...  mechanical engineers have been taught (in the past) to calculate strength and then triple the values for safety.  in software, this is equivalent to tripling the test cycle with random inputs.  instead, we ship software that barely passed a smoke test... 

I also have a pet peeve: engineers should be taught history of engineering, from Chaldeans to Romans, to industrial revolution.  But that is not going to happen....

My understanding of the cosmetology license is that it more than anything else a money-maker for the certifying board, and most likely was put into place to minimize competition. My wife does just as good a job at cutting my hair as the "professionals" (albeit taking a bit longer) but could not legally charge people for this without a license. In a similar vein, the cab companies are up in arms because people are using an app that lets them gives rides to others who are going to the same place/same direction -- basically they (the cab companies) are accusing them of offering an "unlicensed" taxi service. Taxi licenses in NYC are very expensive, so I can see how someone might object to me giving a ride to someone else for a much lower cost, but in the end, what is the problem? I don't know what requirements one must meet to drive a cab in NYC, but my last taxi experience (in Chicago) was with a guy who could not speak English, did not know how to get to my desired destination, and even after finally programming his GPS, I had to tell him when to exit the freeway and where to turn! What was THAT certification/license worth? Then the taxi company has the nerve to charge me "meter and a half" because the hotel was in "the suburbs" instead of downtown. Licensing, outside of a very few professions (medical) has never been much more than a way of making money for someone. Engineering is particularly difficult, because there are so many categories and sub-categories. In addition, as we who work in the industry know, certification does not guarantee competence. In the end, in my opinion, certification is way for established organizations to maintain their lock on particular field.

Are you familiar with the economist Milton Friedman? He wrote a book called "Free to Choose: A Personal Statement," in which he enumerates the virtues of free markets one by one. The book has a series of chapters called, "who will protect us from the $some_bad_people," where he one by one discredits arguments for government limiting access to professions with things like certifications. Cosmetology is one of them.

Without answering your question on licensing being inevitable, let me first ask, have you ever seen it make a difference?  I have not.  I have known a number of licensed PE’s and I can’t name one that I thought was as good as some non-degreed software engineers I know.  Then again, PE licensing involves such a broad range of requirements it seems to be more a jack-of-all-trades, master-of-none situation.

This is along the same line as our not requiring a specific degree for our engineers.  I would rather hire someone with the passion for the work and the demonstrated ability than someone who managed to pass the required classes.  I have worked with far too many MS and PhD degreed engineers that were nearly incompetent where it counts.

I've come to see professional licensing as a way for unions to gain a legal method to limit competition. In most cases it seems to me that the profession are the ones being protected, not the public, as the licensing authorities would want us to believe, as justification for the rules.

Many years ago, the IEEE had a leaning toward licensing. I believe their prime motivation was to protect US workers from foreign workers. Another protection they seemed to promote was the limitation on work visas and such.

This is why I dropped my IEEE membership. I feel that I would be a hypocrite to support this and yet support free trade, oppose unions, etc. It would be against my political and ethical beliefs. On a side note, I believe that, for instance, the AMA is significantly responsible for our health care mess. It seems obvious to me that allowing an interested party, (doctors), to control the number of new doctors on the market is a great way to drive up medical costs. Another great way to drive up medical costs is to let doctors decide that I must visit one and get permission, before I can purchase a needed drug, such as blood pressure medicine or athlete's foot cream, or birth control pills, etc.

Anyway, it would seem to me that requiring licensing of embedded developers would serve me from a selfish point of view, but would not serve the public, quite the opposite.

I suggest that we police ourselves possibly, by having a private certification authority. Advertise this authority and get the public to recognize it as an organization dedicated to quality. Then have it funded by engineers who agree to their standards and pass a test or something similar and pay for membership. Membership to the organization would be a great stamp for your resume.

I think real estate agents, real estate appraisers, boat appraisers, jewelry appraisers and many more use this business model.

Why couldn't we?

Finally - the license business is wrought with self interest as evidenced by the requirement of things like licensing to wholesale liquor, to sell caskets (both of which have lost court cases here in Ga), and such silly things as licensing of flower arrangers in La and as you mentioned, licensing of barbers, interior decorators, the list goes on...

There is a balance between certifying the developer, and certifying the company and certifying the product. I have no certifications beyond university degrees. But the company I work for has ISO (and other) certifications

The products I work on under go many very rigorous certification test regimes for vibration and waterproofness, security, interoperability, RF noise, RF band compliance, intrinsic safety in hazardous atmospheres, ..... the list is very long and very comprehensive. Some tests are external, some done by a large internal test team.

The people who perform certification tests have the appropriate certifications.

Doctors need to be certified since their effects are "In Real Time". I don't need to be certified since certifying my outputs is a more effective procedure for controlling risk.