Nothing ages a bathroom like gray, yellow, or moldy grout. If yours is clean but discolored from years of moisture and grime, give it a refresh with a grout pen. If you can color within the lines, you can use a grout pen. Simply run the tip of the pen along a line of clean grout to restore your bathroom or kitchen tiles to pristine condition. And, your grout will stay cleaner looking for longer thanks to the grout pen's antibacterial formulation. Available on Amazon; $7.80.