Actually this is more like a Braava, which is the mop version of the Roomba, but everyone calls them Roombas so bear with me. Went with a Braava because they are taller (due to the water reservoir), also the Mouse Droid looks more at home on smooth floors than on shaggy carpets.
Removed the spiky things on the roof to make the reservoir friendlier to access. Also cats like to ride these things so may as well make it flat on top.
Originally I designed this to be a Roomba but those vacuums are designed to sneak under couches and chairs, and the Mouse Droid is simply too tall.