I use hydor's flow nozzles. It hooks straight up to my pump outlet into the tank (2 outlets, actually). Is this what you are all talking about? Or is there an actual powerhead they make too?
The flow nozzles are great. They use what you already have... no power consumption. Hooks up to most round outlets (comes with different size adaptors). Provides 360 degree rotation with about a 30 degree bend in the water flow. If you picture an icecream cone shape in 3D, thats the rotation it gives the water flow. Pretty nice for the cost and you just clean it once a month or so.
Edit:
Was going to tag a picture on to this so you could see it, but it came out kind of dark. I used paint to outline it so you could see it better... that's when I sat back and viewed my work... and I thought better of the post. Anyone who has one of these nozzles will get the joke.