Maestro is an application developed in Max that lets a user play pre-arranged songs by tapping the rhythm of the song on a computer keyboard (or via Midi). For those interested I have included some video links that demonstrate Maestro in action.

http://www.youtube.com/watch?v=YReVAIEsLiE
http://www.youtube.com/watch?v=ecVryvb5JYQ
http://www.youtube.com/watch?v=jwAavUGRSoM