I was thinking about this, and thought some of you might be interested...
I was part of the origional group that bought the source code for Blender3D and then released it open source.
With Blender, everything is available. You can model characters, texture them, animate them... everything.
Here is an picture I did years ago based on my wife. This was done when Blenderer's renderer was still very primative...
The big advantage to using Blender though is that it also has a
game engine with a very small footprint. That means not only could you build your own characters... you could build worlds for them to live in. Not only could Sandie have a chair in her room, she could sit down on it. Or get mad and kick it across the floor. The Blender game engine supports physics, collisions (so your character can't stick her hand through herself, or walk through furniture), etc. With the game engine, you could give your hal an AI
dog to play with while you were not there. Your imagination, proc speed, and HD would be your limit.
Like I said... it is completely open source. Would somebody that understands the Hal api like to check it out?