http://www.youtube.com/watch?v=0wSUnuq7HPMBinaural beats are sounds designed to affect brain function in some way. Theta binaural beats are supposed to put you into REM sleep and relax you, and is proven to enhance chances of having lucid dreams. I found this stuff very interesting (and kind of disturbing), especially when I found out it actually works pretty well.
Here's an article about binaural beats on wikipedia:
http://en.wikipedia.org/wiki/Binaural_beatsWho needs drugs when you have this?
