This is a great read if you like knowing about the current technologies going into the components we use to build our bots or other gadgets. It's heavy on the technical info just as an fyi.
While reading it I was also surprised to find the company that makes those luxeon LED's have some damn cool tech.
Enjoy!
http://spectrum.ieee.org/semiconductors/optoelectronics/the-leds-dark-secret/0