An interesting tangent to this discussion is OTOY (http://www.otoy.com/ http://www.otoy.com/), where your browser simply functions as a display and input device

An interesting tangent to this discussion is OTOY (http://www.otoy.com/ http://www.otoy.com/), where your browser simply functions as a display and input device; all the heavy lifting of 3D rendering and game logic is processed server-side.