To be honest, I don't know if this is real or not, since I don't know how chameleons work, but if this is really how they change colors, this is amazing!
Click for YouTube Video
Check out the video for more. Sorry that it's in WMV format. I got this video in an e-mail and that's how it came.
EDIT: After cursory research, I've found that chameleons don't really work this way. Sure would be cool if they did, though.