...by re-installing Windows on an old laptop. People bring over their computer and I do a clean re-install of Windows so their computer is fast and like new again. It's an operation that requires maybe 10 to 15 minutes of real work and a whole lot of waiting, in which I can do whatever. The best part of this is, is that people are always super happy once it's done and they think I performed a miracle. It's a nice and pleasant way to make a little money on the side.