> some sort of crystal-looking crust on themWe need a photo!
My first guess was one of those flickering LEDs
http://evilmadscience.com/productsmenu/partsmenu/353
photo
http://www.evilmadscientist.com/2012/flicker-leds/
and
http://www.evilmadscientist.com/2011/does-this-led-sound-funny-to-you/
Presumably a P/N generator using a shift register.
But you describe something entirely different, some kind of crude electrochemical reaction?
......... Zim
Edited by - gzimmer on 1/12/2013 2:21:57 AM