Unlike the better-known Roomba, which cleans at random, bouncing off furniture and redirecting itself, the Neato XV-11 vacuums strategically. It surveys the room with its infrared laser range-finder, taking 4,000 readings a second and measuring the distance to every object within 15 feet, and repeats this reconnaissance from several vantage points until it has constructed a bulletproof plan of attack. Next it goes to work, vacuuming around the perimeter of the room and then taking out the center, zooming up and back in neat rows.

It scans constantly for new obstacles as it moves, so it won't be defeated by a surprise cat or toddler. Laser navigation conserves battery life, allowing the vacuum to cover new ground with every sweep instead of hitting the same patches over and over. The XV-11 devotes 80 percent of its energy to vacuuming - a feat worth saluting.

$400; neatorobotics.com