The pattern generated after collision is unexpectedly beautiful!
http://technology.todaysbigthing.com/2009/08/04 (via Metafilter Vortex smoke ring Collision. Wow! | MetaFilter)
Cool. I can imagine two galaxies colliding that way, if all the variables are just right.
It seems almost fractal as the rings make smaller rings which make small rings. At least until they lose definition.
I wish they had a slomo version. That was fascinating.
That must have been a tremendous collision, what with the way it shook the camera.
Download mpeg version here Doména je zaregistrovaná and use a video player with slow-mo. (from here http://lofi.forum.physorg.com/Matter-Composition._4201.html, linked from Mefi comments.)
The result of the collision vaguely reminds me of Conway’s Life.