An interesting way of creating displays by taking advantage of interference effects similar to the way butterfly wings generate color:
http://www.iridigm.com/tech_overview.ht
It's also nice because if pixels in the display are not changing, the display requires almost now power; power is used mostly to change pixels. This is much better than LCD and CRT displays which draw the same (large) amount of power regardless.
Slashdot discussed this technology: http://slashdot.org/article.pl?sid=02/1