I hate lens cleaning cloths that are sold in camera stores.  Maybe I am just a klutz but I always seem to add as many smudges as I remove trying to use one on a lens.  And on a filter, they are never big enough to clean both sides at once and they force you to hold the filter by the edges and try to keep a grip while getting it clean.  I long ago gave up on the tiny things and now use the iKlear.  I originally bought it to clean my laptop screen and discovered that it is just as effective at cleaning lenses.  The "microfiber chamois" and "microfiber terry cloth" towels are a little larger than a standard washcloth.  I use the chamois on my lenses and filters and the terry cloth on everything else.  At $15, it is roughly twice what you would pay for one of the tiny cleaning cloths.  If you need a last minute fathers day gift, you cant go wrong with the iKlear.