Try sculpting with clay. The materials are really cheap (50lb bag of WED clay for like $20, or a 1lb block of Sculpey for $10), and you don't really need a creative bone in your body. You can build whatever you want, then destroy it, or bake it and keep it. It's like Legos for adults that doesn't hurt when you step on. And who knows, you may get good at it and invest some money in bronze casting...turn your hobby into a lucrative career.
