A friend of mine emailed an excellent link to Japanese videos of Rube Goldberg Machines. You can see them here:

http://www.ebaumsworld.com/videos/rube-goldberg-machines.html

It is very nerdy, but I can be easily entertained. It reminds me of the Gravitron in Canberra's Questacon. I would sit for ages, just watching all the different permutations. It really is mesmerizing. You can take the virtual tour, and catch a glimpse of what I mean:

http://virtual.questacon.edu.au/