See the feature highlights for the Unreal Engine 3 from GDC 2012.
Kite is a cinematic created in Unreal Engine 4 and features a diverse and beautifully realized 100 square mile landscape.
Unreal Engine - Free
Today Epic Games have announced that their Unreal Engine is now free for all uses, with a 5% royalty.
Unreal Engine 4 - Rivalry
Epic's Unreal Engine 4 Rivalry project shows what's now possible on mobile devices.