http://angel.elte.hu/~andras/lb.html
Who doesn't love floating multi-colored plasma balls?
edit: right, i forgot the warning (and it deserves to be reproduced):
Warning!
These experiments are dangerous. If you are not an expert of the field DO NOT EVEN THINK ABOUT TO REPEAT THESE EXPERIMENTS! It could demage your microwave oven, your kitchen and kill you!
but, if any of you ignore that, I still want pictures.