garrysmod (gmod) is a mod to play with the HL2 physics,
and it can do many more by using LUA scripts.
but it is this scene he made for the picture, it doesn't make any sense and is kinda weird.
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My System: C2D E6700 @3.4ghz | Asus P5W DH Deluxe | 4GB DDR2 800 | eVGA Geforce GTX 260 55nm SC-Edition
Tutorial: Hardware Antialiasing in PCSX2 (DX9 only)