When robot vacuums debuted, early adopters bought into the idea that they could let the devices loose in the morning and return home to spotless floors. That was not the case.

Improved tech has made robot vacs worth buying, and the best we've tested is the iRobot Roomba 780, at left. It works surprisingly well, navigating multiple rooms and attacking piles of popcorn and cereal with dogged, mechanical patience. It's even intelligent enough to sense and target extra-filthy areas for multiple passes, recleaning until all crumbs are accounted for.

As well as the Roomba sucks up debris, it doesn't make your floors shiny. For that, the Mint Plus  doesn't vacuum, but it does mop floors spotless with its reservoir pad. [$600; irobot.com[$300; mintcleaner.com]