"Unreal Engine now runs in Flash and Crytek is considering porting CryEngine to Flash, but perhaps the Source Engine could go a different route. A software developer who works for Motorola Mobility has managed to get the engine and a level from Team Fortress 2 running in a browser using WebGL. There are still a few features and effects missing, but he claims it achieves a solid 60fps and has a video to prove it. Hopefully this gives Valve ideas; it'd be cool if older Source games became playable in your favorite browser, or even directly in Steam."