explokate

Hi everyone, We're planning a party and we'd like to make some science demos to use as centerpieces at the dinner tables. Ideally, these would be: - interactive - pretty - fairly cheap or easy to make ourselves (<$100) - safe and not messy For example, one idea is a ferrofluid display cell along with some magnets, but it's hard to get good information on how to make these. An open dish of ferrofluid would be too likely to lead to disaster. Another idea is something like this demonstrating eddy currents: http://www.exo.net/~...ngincopper.html but that seems to be prohibitively expensive with the price of copper as it is now. Any other ideas would be greatly appreciated!

Any updates from anyone who has tried it? We'd like to make a demo cell, just for fun. In particular, if the FerroTec EFH1 is put in vodka as the last poster suggested, how long does it stay pretty? Does it mix or degrade eventually? Any expert advice out there from others who have tried this in the meantime?