Some Formica stains are more stubborn than others. Grass stains, coffee, food dyes and watermarks can be tough, but still manageable. Newsprint and many inks will be a bit tougher. Hair dye is on the list of stains that could be permanent, but with a little help from some nail polish remover, you could achieve the near impossible. After you've tried the other methods listed, including the overnight baking soda paste soak, brush some acetone nail polish remover onto the stain with some cotton balls. Before using it on a colored countertop, test it out in a hidden corner and see if it changes the color. If it does, you might want to just live with the stain. If it seems like it will work, though, try it out, and then wash down the counter with some soap and warm water.