Mozilla is working on porting several new things to the web. For example the Unreal Engine 3! So in the not too far off future we could have good looking games on the internet, no more of that runescape crap!
The guys over at Mozilla is even porting Bullet, the physics engine in Blender!
These guys are so awesome so they have even posted several demos of what they are working on.
Visit emscripten here:
I encourage you all to take a look, theres not just game related stuff there, they have been busy with alot of other things aswell.