Little Star Electronics via eBay offers the Boombotix Boombot Bass Station Bluetooth Speaker with 15-watt Subwoofer Dock, model no. BSTNBLK01, for $19.99 with free shipping. That's $5 under our September mention and the lowest total price we've seen. (It's the best deal now by $10.) It features a 2GB flash drive for music storage, Siri and Google Voice controls, water resistance up to 3 feet, dual-amp stereo sound, and a 15-watt subwoofer dock that also acts as a charging station.