MP4 Nation offers the SoundMagic MP21 In-Ear Headphones for $22.50. Coupon code "fb2012fiver" drops them to $21.37. With free shipping, that's $22 below list and the lowest total price we could find, outside of the mention below. They feature an inline microphone and remote, 9mm drivers, four sets of ear tips, gold-plated plug, 15Hz to 22kHz frequencey response range, and travel pouch. Note: It ships from Hong Kong and should arrive in two to four weeks.

A close price: Massdrop offers them for $19.99 with $2.55 for shipping.