I don't know if you could really call it a gadget, but Mr Clean Magic Eraser is the BEST THING EVER! I had heard about these little foam-type pads a few months ago, but never had any reason to use them until our trip back to Colorado to clean up the townhouse after our renters made a giant mess of it. The walls were covered with various marks—scuff marks from shoes, furniture marks, marks of unknown origin—and we thought we would have to repaint everything. We picked up a pack of them at Home Depot and were AMAZED with the results! Now we don't have to repaint the entire house (we still have to paint the master bedroom, but that was beyond repair...).