Dishcloths and cleaning rags can get pretty grimy over time, so I like to give them a thorough, deep cleaning every now and then. To do this, I simply take a load of them and soak them in a solution of boiled vinegar and a few drops of Dawn dish soap. I let them soak for an hour or so, then toss them into the washing machine with laundry detergent (any brand you prefer or have on hand) and a good sprinkling of baking soda. After that, I run them through the dryer. Any smell that they had is then gone and they're thoroughly fresh smelling and clean!
You can't beat baking soda for a fresh, clean scent.