I'm no entrepreneur, but I think you should consider just finding stuff you enjoy and where you'll meet people with common interests. E.g. if you like dancing, join a dance club. It won't help you out in the future, but once you graduate, its likely you won't have a lot of time for a dance club afterwards.

Might sounds a bit cliche, but still, I think that spending all of your college life focusing on your future career is a bit of a waste (thats my opinion anyway).