Secondipity via eBay offers the refurbished Sony NFC Bluetooth Wireless Portable Speaker, model no. SRS-BTX300/BLK, for $54.99 with free shipping. That's $45 under the lowest price we could find for a new unit. Features include one-touch Bluetooth pairing with NFC, speakerphone functionality, and up to 8 hours of battery life.
A 90-day warranty applies, although it's unclear who supports it.