Robomaid

Robomaid is a low tech, very cheap version of Roomba cleaner. It doesn't clean rugs, but has done a great job on our wood, tile, and stone floors. The design is wonderful in its elegance: a powered ball propelling a sweeping "hat". Like Roomba it cleans along walls, under tables and desks, and in corners where it would be difficult to clean otherwise. It uses no intelligence, so it randomly changes direction, but is surprisingly thorough. Especially since I don't care how long it takes. It has some lovable quirks: you need to block it from going down stairs (going down the stairs has not damaged it, but I worry). It does not find its way back to its recharger when done, so you need to locate it after it has cleaned. The electrostatic cleaning pads need replacing after 5-10 cleanings, and cost 30-40 cents each, so the cost per cleaning is 3 to 8 cents. I got it for Christmas from friends who thought our pets would enjoy it. I had low expectations. Our pets ignored it after the first time, but it cleaned so well it has become a fixture around our house.