http://youtu.be/BQAVRxoO2Wc I'm not sure if this belongs in science and technology or the stoner's lounge, lol. I thought I'd easily find lots of cool flow visualization videos on youtube, but only a few so far. Please feel free to post cool flow visualization videos here!
I like these, they're good homeschooling tools. There was one I liked on the website of a cold spring we went to, but I don't remember how to find it.