A jar (Petri dish I think it was) 1/2 full of liquid A. A single drop from an eyedropper charged with liquid B was dropped in the middle of liquid A. Immediately, liquid B dispersed to the sided of the Petri jar (ie horizontally)!
It could be something dispersed from liquid A to the sides - am not sure. But the effect was dramatic anyway. Wish I could recall what the liquids were - or even what the experiment was all about. Anyone?
Did I just imagine it all!