- Carbon fiber fabric. Used for making very stiff, strong, lightweight panels. My understanding is that the aircraft industry has first dibs on all production. Also, the quality requirements for aircraft are far higher than for, say, automotive body panels. This means that carbon fiber panels are a lot more expensive than they should be.
- Aerogels. Would make *terrific* insulated windows. They would have a higher R value than the wall that they're set in. I think that with the latest aerogel technology, you could get a solid object that is lighter than air by filling them with hydrogen or helium. Great demo!
- Blue LEDs. They shouldn't work, but they do. Figure out why. Semiconductors depend on the perfection of their crystal structure to work. Blue/UV LEDs are just jam-packed with imperfections, but they still work. If you could get rid of the imperfections, they'd probably work a lot better.
- High-temperature superconductors. The theory still isn't worked out very well, and "traditional" applications are difficult (you can't draw them into wires, for example). Magnetic levitation is a possibility. Energy storage? Motors? Put a big current through it, drop the temperature to the critical point, and you've got a "permanent magnet" that might be able to compete with rare-earth magnets.