Don't recall seeing this mentioned on math-fun: In Jan., there was an article in the NY Times about how when a chain stuffed into a container open at the top, and one end is tossed over the side with lots of room to fall (e.g., letting it drop over a balcony), the chain falls into a pattern with the chain initially rising surprisingly high before it falls -- looking like a fountain. If you don't want to hear the explanation right away so you can think about it, stop this video soon after 1:00. (The explanation begins soon after 1:15.) http://www.nytimes.com/video/science/100000002747620/fountains-of-chain.html... (1 minute 47 seconds).* Even with the explanation, I still find this amazing. --Dan __________________________________________ * Unfortunately, to watch the video you apparently must watch the ad before it, but I didn't find this too painful.