Are there any 3d simulators ?

I was wondering if there are any 3D simulators that you can download / buy?
If so, please provide some links and tell what you think of it?


Well huh, I hadn't thought about that at all! That's an interesting idea. I haven't seen any personally, but it does remind me of wind tunnels that are supposed to simulate it, so I think I'll start a new thread on those, too.