I'm really terribly sorry this is so incredibly slow. I don't know how Mozilla managed to make JavaScript ten times slower than Perl, but I guess JavaScript just isn't the best possible language for numerical simulations. Consequently this isn't as captivating as the Perl+PostScript version was.
Frame #none yet. Running at ??? time units per step; each step takes ???ms to calculate (???ms avg so far) and ???ms to draw, then ???ms after drawing doing other unknown things. (To keep from bogging the machine down, there's another idle pause after that, of ???ms.)
If this line is right underneath the other text, without several lines of space in between, your browser probably doesn't support <canvas>. If there aren't dots moving in it, maybe your browser has some other problem, like having JavaScript turned off, or maybe my code is broken.