My father worked on old cars in his garage after work and on the weekends. On the weekend, friends would flow through for a chat and to help out a bit. Sometimes a friend would bring over one of their own projects. Dad's shop was a minor social hub. He never seemed to finish any of his projects, but I'm not sure that was the point. He wanted something to work on during his spare time.

This isn't for everyone, of course. He had loads of money sunk into tools and he needed a house with a shop (larger than a garage.) He did get some return by flipping some of his projects.