I don't know the actual number- but as a street singer I play an average of 8 hours a day- a few years ago a friend of mine challenged me to play a full 40 hour week without repeating a single song, and I did it with many songs to spare! I think the count is around 1000 (in easy access memory) and another 500 or so that I can dredge up, if I have a half hour to think about it!