This issue's tip is from Phillip Elliot of Elliot's Hardwood Floors in Palmer, Alaska.
Years ago I was sanding a floor and had to sand way under a large stone fireplace. I didn't want to do it by hand, so I came up with an idea to use my Sawzall, a scraper blade, adhesive-backed Velcro, and the Velcro-backed sandpaper. You just have to remove the guard on the front so the metal doesn't dent or scrape the wood, but now I keep this Sawzall dedicated to this purpose only. It works great for sanding under stone, fridges, stoves or other hard-to-reach places.
See this trick in action here: