http://www.brainmetrix.com
Free brain training exercises and games.
They are fun, some of them are addictive and some are intense. So be careful!
Post your scores, please.
I haven't tried them all yet but here's my scores for the ones I did try:
Memory: UPDATE! Just beat level 7.
Brain Reflection: 0.323
Brain Creativity: Stuck on Level 19
Warning, that Brain Creativity game is fun and addictive. Try it, but don't overdo it.