Korean site AVing reports about a floor cleaning robot called Mr. Cleaner.
In contrast to the Electrolux Trilobite or Roomba Robot the Mr. Cleaner is dusting not vacuuming the floor.
The Mr. Cleaner robot can operate 2 hours on a single charge. It sells for a low 98,000 won (~100USD) in Korea. It does not seem to have very smart electronics as far as I could translate the article, the price is also supporting that assumption.
More details and detailed photos on AVing (Korean).