iRobot – Roomba 877 Self-Charging Robot Vacuum – Black/gray – is only $379.99 today on Best Buy as a Deal of the Day — list is $599.99! This is more powerful and cheaper than the last time posted (Amazon). Keep floors dirt-free with this iRobot Roomba robot vacuum. Its AeroForce three-stage cleaning system agitates, extracts and suctions to eliminate stubborn dirt, and its iAdapt navigation feature uses multiple sensors for precise mapping and vacuuming. This iRobot Roomba robot vacuum includes a Virtual Wall Lighthouse beacon device for automated room-to-room cleaning.