Limited 3D Modeling.
Still pretty useful, although there are limits to how ambitious your scenes can be! (Especially when using Maya 6.5, with it's 2GB memory limit!)
Still good for the production of pretty complex assets to be placed in more complex scenes and rendered using the likes of Blender on more modern hardware. (I like Maya 6.5's User Interface, making it easier to use than Blender to perform certain tasks!)