Amazon has the Tribit MaxSound Plus 24W Portable Waterproof Bluetooth Speaker (Black, 5962898564) for $39 with free shipping. List price: $33. Features up to 20 hours of battery life, IPX7 waterproof, secure connection and lossless wireless sound at a range of up to 100 feet. Has excellent Amazon Reviews.
eBay has the Bose SoundLink Mini II Portable Wireless Bluetooth Speaker for $100 with free shipping. List price: $200. Features built-in microphone, 3.5mm auxiliary port, up to 10 hours of playback per charge.