Just got the fluid simulation code I've been working on to the point where it works correctly. Until I get something more impressive, enjoy this video of a dot vortex!
If you're interested in playing with this yourself, check out the excellent articles by Dr Michael Gourlay over at the Intel Software site.
I should note, this simulation has 27000 particles in it, and runs at 60fps while using about 60% of one of my cores (on a 3.33Ghz c2d). That's without any optimisation, and full debug symbols compiled in.