Meritline offers this OrigAudio Rock-IT Portable Vibration Speaker, model no. ROCK-IT-WH, for $21.99. Coupon code "MLCK529GNL1" cuts it to $16.99. With free shipping, that's the lowest total price we could find by $3. This speaker works with any audio device that has a standard headphone jack. It comes with a USB cable and requires two AAA batteries (not included.) Coupon expires after 50 uses.