See the Unreal 4 engine in action in this trailer for Primal Carnage Genesis.
Real-time Global Illumination with Enlighten and UE4
Epic Games and Geomerics created the video to highlight the latest physically-based lighting techniques in games.
Unreal Engine - Showcase
This compilation video shows off some of the games built wih Unreal Engine technology.
Eat 3D - UnrealScript MasterClass - Part 3 - Re-creating Assault in UDK
Eat 3D have released their 3rd DVD in the UnrealScript Masterclass Series, focusing on re-creating Assault in UDK.