I was aware of ferrofluid to cool speakers

http://en.wikipedia.org/wiki/Ferrofluid

Now someone has the idea of using it to make the
speaker itself, including an LED show

http://www.newscientisttech.com/article/dn9520

(caution - many side-tracking links)

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist