Humans have already built a pinball machine this small.
What comes to my mind as a strong future technology is micro airplanes and micro mobiles, and micro machines, and micro mail delivery, and micro helicopters that deliver small than mini-sd sized memory cards to my door, and micro machines instead of just transitors and chips in computers, and robots that are composed of replacable micro machine cells and micro components.
As a machine, parts can be repaired. As a living being, parts are harder to repair. A regular mosquito only lives a short life - but a micro robot that looks like a mosquito but isn't one, may be able to last much much longer than a living mosquito.
Unfortunately micro/nano sized machines can be used for both constructive and destructive purposes.
A micro machine mosquito robot should be able to travel from germany to Canada or from Sweden to France, or even from city to city or state to state, or province to province. The micro machine can stop along the way to replace some of its worn out parts. It should also be able to stop along the way to eat sugar and water for fuel and lubrication (or ethanol and cooking oil). It could even be able to use soap as lubricant, since soap is in almost everyone's home.
So imagine this robot mosquito - injecting each person in a certain city or country with poison. Or imagine it doing something productive and constructive like bringing messages mechanically instead of digitally through email (for more secure delivery, and cheaper than the post office, use mosquito mail!).
The mosquito may be good for air travel - but micro machine ants without a soul may be good for slavery. We program the little micro machine ants to build us things that normally USA and other countries would outsource to china children.. tight and small little knit hacky sacks, shoe sewing, shirt sewing, tiny mp3 players (we just lost another worker ant that starved to death! shit! oh well, at least he doesn't have any soul, and no life insurance, and we don't pay him any salary).
Many people underestimate the power of micro machines. This little pinball machine seems to be taken as a joke or a gimmick. It's kind of like how people have underestimated the power of the internet in 1995 or even 1985 - and these folks only woke up in about year 2003-2004 or so - some are waking up now in 2006-2007 still yet.
How long will it take, before people understand the power of micro machines?