Amazon offers Prime members the Creative D80 Wireless Bluetooth Speaker in Black, model no. 51MF8130AA002, for $19.99 with free shipping. (Non-members can spend $35 for free shipping; otherwise, it adds $7.32.) That's the lowest total price we could find by $25 and a very good price for a new unit. Features include two 3" drivers, a wireless range up to 33 feet, toggling between two pre-paired devices, and AC power cord.

Note that this item is temporarily out of stock, but can still be ordered at this price for delivery when available.

Update: The price has increased to $24.99.