I've been in touch with Cliff Medling from 3DVia, who has some pretty cool, free tools to visualize 3D models as a walking (and running) avatar. This video is intriguing:
I'm out of town at a conference, so I've only had bits and pieces of time to play with 3DVia scenes. In my limited time so far it's been a very cool experience, but I'm having a tough time maneuvering around as smoothly as I'd like. For instance, once I get in a corner of a room, I have a hard time getting out!
Once I get a presentable scene going I'll post about it. And I'll probably write up some instructions as one of my monthly plug-ins. In the meantime, give it a try yourselves...
Anyone can design anything in 3D! http://www.3dvinci.net/