Biofeedback is popular among amateur, Olympic and professional athletes to find and stay in The Zone: calm and focused.
Wall Street Journal Article on neurofeedback.
Presentation of research at the 1997 Winter Brain Conference. 14 of 15 golfers reported significant improvement in golf scores.
"Tuning In" is a 3-year effort to discover what works to improve performance of musicians. Only one thing works in rigorous double blind studies: neurofeedback.