Epic Games posts a tech demo for the Unreal Engine 3, some crazy stuff! Be sure to check out the newest beta releases of the Unreal Development Kit (UDK) which is a free edition for educational or non-commercial use.
Check out the new Unreal Engine 3 trailer! This highlights just a few of the engine features that help developers create gorgeous environments.
UDK is Unreal Engine 3 – the complete professional development framework. All the tools you need to create great games, advanced visualizations and detailed 3D simulations. The best tools in the industry are in your hands.