The Yamaha NX-B02 portable Bluetooth device is a 10W stereo speaker that runs on 4 AA batteries or with the included AC adaptor. Range is 15 feet when using Bluetooth 2.0 + EDR (Enhanced Data Rate) with A2DP compatibility. There's also a 3.5 mm stereo mini jack for connecting to the speaker with a wire. Dual 1.75 inch full range speakers are 5W each and incorporate a specialized bass diaphragm to deliver deeper sound. MSRP for the NX-B02 is listed at $199.95, however we've seen prices online as low as $100.
Logitech's Pure-Fi Mobile speakers connect wirelessly to your iPad using A2DP (stereo) Bluetooth. With a range of 33 feet (10 m) and dual 2-inch (5.1 cm) active drivers and 2-inch (5.1 cm) pressure drivers, the Pure-Fi Mobile provides quality sound anywhere. Built-in batteries last 12 hours, and a 3.5 mm jack can also be used for input. The unit can even act as a computer speaker, getting audio and power from a USB cable, and includes two built-in microphones. Pure-Fi Mobile comes with a padded carrying case and can be found online for $125.