I was at London Drugs on 8th last night and bought a Dirt Devil Whiskers robot on for $49.99.
Its no Roomba but it cleans ok on hard floors. It has the vacuum and 2 side spinner brushes.
Would make an decent hackable robot development platform. Comes with NiMH battery/charger. gearmotors/wheels seem reasonably powerful. Front bump sensor and 3 adjustable floor IR sensors. The dirt bin in mounted in the top middle, if you remove it there is space to install your own electronics and whatnot.
