Spot is a dude. Not in the traditional sense, although he is very studly; he is a skeleton for an autonomous animated character (nicknamed a "dude"), or a model with an attitude.
Spot was written in Eve, a language created by Michael B. Johnson (firstname.lastname@example.org). Eve is essentially Tcl with a RenderMan binding. This allows models to have state variables that can be modified by the user or controlled by behavioral agents.
Spot is an example of malleable media, in that he has several different ways of being controlled. The user interface to Spot (there are currently no agents controlling him) was created in Interface Builder on the NeXT. Users can select a predefined emotion (as seen above from left to right, "Cool", "Sad", and "Angry"), modify "emotion" parameters (i.e. degree of sadness), muck with the model itself (i.e. changing the thickness of the shades), or move a virtual object around the scene and watch Spot's surprise as the result.
Kenneth B. Russell - email@example.com