World Wide Stereo via eBay offers Able Planet Extreme Noise-Canceling Stereo Headphones in Green (pictured), model no. XNC230G, or Red, model no. XNC230R, for $34.95 with free shipping. That's the lowest total price we could find by $5, although we saw them for $5 less two weeks ago. These headphones feature active noise cancellation and 20Hz to 20kHz frequency response and require one AAA battery (included).