We hate our cat's litter box as much as the next cat owner, which is why we're always on the lookout for ways to decrease the eau de toilette that wafts around our apartment. We've yet to find a solution that really works. One Instructable user went to the extreme to come up with a solution by building an exhaust fan within his kitties' waste disposal area. While we don't think we'd go to such an extreme, we do appreciate the measures that this cat owner went to control his kittyies' odors. Daniel Bauen built his litter box exhaust with a computer fan that continuously draws a small amount of air out of a covered litter box and pushes it through a dryer hose which then expels the air outside. "The hot/cold air loss to the exterior seemed to be pretty minimal, because there is no noticeable change in heating/cooling costs," he writes on Instructables.
The computer fan is quiet enough that it doesn't freak out his two cats and can be powered via solar powered batteries -- Daniel has an Instructables on just that.
We could see this working well for homes with laundry rooms where you don't mind another dryer hose snaking through the room.