I would not keep 100$ that I found. Even if I needed a decent thing. You could get a reward if you return money they might even let you keep it. If you keep it you could get in big trouble. So if you return the wad of cash you have to convince them you did not steel it.return the money.If you fined a peeney I am sure they will let you keep it.If you need money just make a fun raser.