maya is one, i prefer it, blender(free iirc) another, milkshape is a good simple one for doing quake/half life style animations and is free.
poser will get you a good start, some of the fractal designs stuff has nice 3d painting where you can skin quickly over existing models.
and theres always 3ds max, if you absolutely have too
theres a lot of plugins for it to do animation, bones pro, bonesjiggler etc
pixels 3d mac only