I want to strongly recommend that everyone check out
Lumosity - Brain Games & Brain Training - Lumosity and see the brain training exercises that are available there. I've been doing them for about 6 months and I think I feel a difference. It challenges your thinking skills and keeps you sharp, and are pretty fun too. Check it out. Read the research. Play some of the games. And decide for yourself. Lumosity exercises are designed by neuroscientists to improve core cognitive functions.
Researchers have measured improvements in working memory and attention after training.
It enhances memory, speed, flexibility, attention, and problem solving.