You can get this sub for $250 from World Wide Stereo using coupon code "XRY34Y". I don't know when it expires.
Mirage MM-8 Compact Powered Subwoofer - High Gloss Black at World Wide Stereo
At 9" cubed, this is categorically competition for the Velodyne MicroVee reviewed here:
MicroVee Introduction & Design Overview — Reviews and News from Audioholics.
My guess is it would offer a wee bit more extension (larger driver), but not as much SPL (not as rigorous of a design) as the Velodyne at a much lower price point.
One of the reasons to post Gene's review of the MicroVee is so you will understand the limitations of such a tiny sub.
Please recognize that this is only a good option if you have extreme space restrictions and are looking to augment small bookshelf speakers (Audio Engine, for example) for music (it'll probably provide bass equivalent to a normal sized bookshelf speaker).
This is a great price if it fits your needs.
The specs say 9" cubed, but I'm pretty sure that is the main box and does not include the feet or the connections and knobs on the back.
