Very informative site detailing healthy use of computer keyboards, mouse, Blackberry etc with specialist Edna Golandsky. These principles of seating height and healthy use of fingers,hands and arms can be applied across the board, including playing your instrument. Pianists might be interested to note that this approach to computer use is directly transferred from the Taubman Approach to piano technique www.golandskyinstitute.org
Quite a few sfree hort YouTube mini-lessons, in addition to a lecture and three lessons that can be downloaded for an introductory price of US$25.