Today only, October 1, 2011, Woot has the iRobot Roomba 530 Robotic Vacuum with Virtual Wall for $159.99 ($299.99 if new). Shipping adds $5.

With dramatically improved navigation, cleaning coverage, vacuum pickup, and particle filtration, the Roomba 530 vacuuming robot picks up amazing amounts of dirt and debris with the simple touch of a button. The powerful unit features innovative spinning side brushes that grab dirt and dust from corners and along wall edges, as well as two high-speed, counter-rotating brushes that pick up pet hair, cat litter, food crumbs, and other debris from floors. The vacuum sucks up the debris and deposits it into a large, easy-to-empty bagless dustbin, and its improved fine-filtration system traps dust, pollen, and other allergens inside the unit, reducing infiltration into the living environment.
For added convenience, the vacuum’s cleaning head automatically adjusts to transition from wood, tile, and linoleum to carpets and rugs, while improved anti-tangle technology ensures it won’t get stuck on cords and rug fringe. If the unit begins to pick up a cord or carpet tassel, it will automatically reverse the direction of its brushes to extract the item. A gentle-touch bumper system senses obstacles so the vacuum automatically slows its approach, gently touches the obstacle, then redirects to continue cleaning under or around the object. Because it cleans under beds, couches, and other hard-to-reach areas, it actually vacuums more of the floor than a standard upright can. The vacuum also senses dirtier areas and spends more time cleaning them, and it uses built-in cliff sensors to avoid stairs and other drop-offs. In addition, invisible barriers can be set using the unit’s Virtual Wall system. To mark off-limit areas, simply place a Virtual Wall at a doorway or other opening and adjust the infrared beam setting to the distance of the opening. The unit automatically detects the beam and will not cross it.

The vacuuming robot returns to its self-charging Home Base to dock and recharge between cleaning cycles or when the battery starts to run low. Its advanced power system consists of a fast-charging battery, a three-hour charger, and a power source that supercharges the unit for up to 120 minutes of continuous cleaning, covering about three to four average-size rooms on a single charge. Other accessories include two Virtual Walls (that require two D batteries each), a brush cleaning tool, and an extra filter. The vacuuming robot measures 16-3/4 by 21 by 5 inches and carries a one-year limited warranty.