Lighting is still white only. Sprites are used for monsters and other moving objects in games. In Crystal Space, the term sprites refers to the 3D Sprites which are actually real 3D objects. Unreal also offers very good AI for the creatures in its game. The creatures actually start acting reasonably smart.
Curved surfaces are the next kid on the block.
Quake III Arena and Crystal Space will offer this. Games are currently the most popular use of those 3D Engines. However, one could easily imagine them being used for architectural purposes. Medical applications often use 3D Engines as well, but those are very specifically written for that purpose. Being comfortable with computers and programming is of course a requirement.