Ask HN: Open source possible product?

Currently, I have a product (Mac, stand alone) that is about 75-80% done. I personally lost interest in it. It is not something I want to follow through (after some research, it would probably return about 25k-30k a year) because I have a day job, and if I'm going to work on something at home it may as well be something I love (games).

My question to HN is, should I keep it quiet? Try and finish it, even if I'm not really happy doing it? Or just open source it? And if open source it (which is what I'm thinking of doing) what license? I don't want people to just pick the code, add a couple things and sell it, but at the same time I don't want to limit it so much that folks can't really use it (I dislike GPL for this).