Ending today, Groupon offers the Roomba iRobot Braava Floor Mopping Robot, model no. 321, for $119.99. Coupon code "TRIPLE" drops it to $107.99. With free shipping, that's $12 under last month's mention and the lowest total price we've ever seen for this model. (It's also a current low by $42.) It features dry and damp cleaning modes and a NorthStar navigation system.