I haven't really done that much 3D art work, but I have fiddled about with programs such as Studio Max and a little bit of Maya. If I am making something in 3D, it's usually in the form of a game map for an Unreal game, this is because I'm very familar with the editor. The editor itself is unlike any other editor, which is why sometimes I'll have problems adjusting to a different editor like DEdit (Aliens vs Predator 2). I like mapping because of the fact that another persona can download it and interact with it completely, even if it means falling into a big BSP error, it's still interacting, I do strive not to have any of those if I can help it.