Samsung WEP870 Bluetooth Headset for $9.99 shipped after this $20 rebate. Here is a screenshot for your reference. It has two modes, one for phone conversation and the other for listening to music with the included stereo ear bud lanyard. It features 6 hours of talk time and 150 hours of standby. Most places have it for about $39 or more.
Originally posted earlier, it has been slightly revised and this is just a friendly reminder.