I never heard of it until you posted.Sounds like an interesting device,kind of like a plunger action.
Here's a video on Youtube.My concern is the bubbles it is producing,water level in the display(it is pushing water and then sucking it back in) and finally,noise.Maybe the poster doesn't have it set up right.
[ame]http://www.youtube.com/watch?v=d5B9-36riwI[/ame]