Beach Camera via eBay offers the AblePlanet Musician's Choice Noise Canceling Headphones in Black, model no. NC180B, for $20. Apply coupon code "CELLSAVE5ON20" to drop the price to $15. With free shipping, that's tied with our June mention as the lowest total price we've seen for these headphones. (It's also a current price low by $24.) They feature a 20Hz to 20kHz frequency response, folding design, and detachable cord.