How did Broken(matt ebb) do this?

this is off the main page here

it says something vague about curve guides but I can’t really follow. I really like the “strange attractors” effect with just the two particles. I want to put this in something with a strict deadline so please help!

I have the blend, but it doesn’t work in 2.42a? Anyway check here:

The way it was done was using a sphere as a particle deflector (recalc normals inside).

It doesn’t opens in my Blender 2.42a on Linux

Broken probably set an empty or so to vortex and then used animated particles setting it so they go into the range.

The file opens, it just takes a long time to re-calculate to particle emiters of 400000 particles each!