Unreal Warfare Tech @ GDC
One pre-scripted demo featured a futuristic dropship sailing down through the atmosphere, and then flying down a long canyon populated by dinosaur-like creatures. The ship's metallic surfaces and the realistic-looking canyon made this sequence impressive-especially considering the number of peripheral objects such as shrubs in the environment. Though this sequence was completely scripted, allegedly a version of the canyon level will appear in Epic's next Unreal game after Unreal II.
I also snagged a couple of more images the other day and put them into the Unreal2 screenshots section.