Simple Javascript Raytracer example,

Speed tests on my laptop:
IE 7.0.5730.13			10.1 seconds
Firefox		9.9 seconds
Safari (win32) 3.1.1		5.9 seconds
Opera 9.60			3.6 seconds
Firefox 3.1b2pre (no JIT)	2.8 seconds
Safari (win32) 2008-10-15	1.0 seconds
Google Chrome	0.8 seconds
Firefox 3.1b2pre (JIT)		anywhere between 0.6-35.0 seconds

From this I conclude that Mozilla's JavaScript JIT compiler is
still a bit broken, but it looks like it might become a Chrome
killer sometime soon.

The code is messy, but do whatever you want with it.
If it breaks your browser, don't blame me.

Go here for something a little nicer looking,
or here if your browser's fast enough to try animation.