Powder acts like liquid when shaken

Did that get your interest? I wish I had a video of this phenomenon, but I couldn't find one. Toner, the powder in laser printer cartridges, is, well, powder. If you have a bottle of it and move it slowly from side to side in the bottle, it stays a fine powder. But if you shake it up vigorously, it will act like a liquid, swirling around in the bottle just like ink.

I should borrow a bottle of the stuff to show you sometime when we gather.