COVER YOUR TRACKS (from popularmechanics.com)
How many times have you been asked to use a coaster? Now you have to find a way to get rid of those water rings on the wooden coffee table.
THE QUICK FIX
Drip a few drops of machine oil on the surface of the wood and mix in some ground pumice (available at home centers) to make a loose paste. Rub the paste around the rings with the tip of your finger until the rings are gone, then wipe off the paste with a damp cloth and dry the surface.
From Apartmenttherapy.com –
To clean rust with a potato, cut it in half lengthwise or crosswise, depending on how large a surface area you want. Dip the cut end in dish soap or baking soda and firmly rub it over the rusted area. If the end of the potato gets slick, slice it off and apply more soap or abrasive. Repeat until rust is removed, rinse, and dry. Apparently this works because the oxalic acid in the potato helps to dissolve rust. You can use it to remove rust from baking pans, knives, and other household tools.