A4C offers the Sony Smart Wireless Headset Pro, model no. MW1, for $19.95 with free shipping. That's tied with last week's mention as the lowest total price we've seen. (It's also a current low by $16.) It features an onboard MP3 player and FM radio, Android smartphone compatibility (for calling, messaging, and other apps), up to 11 hours of talk time per charge, and microSD card slot (32GB maximum).
Note that this item is new; however, it ships in bulk packaging.