Epic Games has released Unreal Engine 4, fully featured toolset with full C++ source code. You can licence the engine for only $19 per month! More information can be found on official Unreal Engine’s website.
This video shows engine’s new features including: Full Scene HDR Reflections, Post-Process Effects, Temporal Anti-Aliasing, Physically-Based Shading, GPU Particle Simulation and Collision, Thousands of Dynamic Lights Per Scene, Redesigned Level Editor, Mac OS X, iOS and Android Support, Oculus Rift Support and many more!
Get started with new tutorials, create your own level in UE4.