www.cfxweb.net has resumed the JACC! This time, it’s round 7, and " Every challenger has to write an applet that has a animated representation of a set of particles. Valid entries could contain: stars, galaxies, molecules, fire, volcanoes, a life form, leaves, or whatever you imagine fits this theme."
Basically, to enter, it’s an applet from 256x256 up to 512x512, which can be interactive (or not), using any JVM up to the current public release from Sun. (no Java3d yet, until it becomes part of the standard jvm ;))
Take a look here http://www.cfxweb.net/modules.php?name=Content&pa=showpage&pid=4 and get yur entries cooking 
Bloid.
PS: There’s no prize…(hehe – that’s becoming a tradition), but if anyone fancies donating a prize, I’m sure it will be gratefully recieved by the winner ;D