It seems like there’s a lot of room for expansion in terms of music software and games. Off the top of my head: Allow musicians to attach their instruments to the computer and play duets with friends or strangers. Use software to practice a song and analyze where you make the most mistakes. Make a game out of it – sight reading competitions, short duets, music battles (ala http://www.youtube.com/watch?v=G-FdX1D5hVg). Vote performances up and down…