Particle Sim [source]

Green Zombies ignore forces
and attempt pincer movements
to infect the others!
Boid behaviour plus 9 forces
Velocity held in pixel RGBA
Up to: A few Tens Hundreds Infestation!

This browser doesn't support the canvas element :-(

Align Center Forces Gap Move Wet Wrap Zombies

Ralative Zombie Speed: 0.5 0.9 1.0 1.5 2.0 Hover mouse for attention.
Tap canvas for new Tiddlers.