In the Id podcast we discussed the fact that Tom Hall was working on Prey at 3D realms after he was booted from Id. Someone has uploaded some early videos of Prey to Google video. It is sort of amazing to look at how far they were along back then, only to have to wait nearly 10 years before getting it released.
Now that Prey is out, I guess they can focus on Duke Nuke'em forever...
Prey Tech Demo (1997)
Prey Tech Demo (1998)
--Chris.