Half-life 2 in real life with HDR rendering

This is called HDR Lighting, and anyone with a camera and a relativly fast computer can make this.
All you need is:
A digital camera
A reflective sphere (which you see in a few photos) to capture the lighting of the real-life scene which you want to composite your model into.
A small program called HDRShop.
Big program called 3D Studio Max.
and finally you need a good renderer such as VRay.
Then of course you need the tools to get HL2 models into 3dsmax: GFScape, a HL2 Model importer, and a texuture and model converter
Tutorial
E46Fanatics - Coolest thing ever, Half-life in real life