The problem with nerds and their hobbies is so many of them (or better stated, us) have hobbies that will NEVER be used in the mainstream. So which ones will?

The problem with nerds and their hobbies is so many of them (or better stated, us) have hobbies that will NEVER be used in the mainstream. So which ones will? Right now my guess is 3d printing is going to be massive in some way or another. It's got that feeling. People love to make shit.