magnetic powerheads

[JeffGil]

I wonder when these will be on the market!

http://www.sciencedaily.com/videos/2008/0608-scumfree_fish_tank.htm

 

[Willy]

They already are and have been for a while now.

http://www.ecotechmarine.com/

 

[Slag]

Here is a video http://www.youtube.com/watch?v=rLPmea2II-A

 

[JeffGil]

Bonus:
http://www.marinedepot.com/ps_Aquar..._icecap_ecotech_marine_vortech_propeller.html

"Optional Battery Backup - Keeps the circulation going during power failure for up to 30 hours."

...but i'm not paying $500 for a powerhead. Bummer.