(The Register) The mini hard drive is already challenging Flash in the MP3 player market, and it now looks like pursuing solid-state storage into the USB drive market too. Sony today launched a new member of its Pocket Bit USB storage product line that incorporates a 2GB micro hard drive.

Sony Pocket Bit Pro USD-2GThe Pocket Bit Pro USD-2G measures 7.3 x 5 x 1.3cm, so it’s hardly as compact as your average Flash drive. But capacity and access speeds should compensate.

The unit uses USB 2.0, with the connector rotating out of the Pocket Bit Pro’s casing, not only to protect it when not in use, but to make it easier to connect the drive to a host computer.

If the Pocket Bit Pro’s size makes it sound rather like a screen-less PDA, its automatic data synchronisation will strengthen the association. By pushing the unit’s AutoSync button, the user can back up a selected folder and sub-folders. Storage capacity permitting, AutoSync will retain up to ten generations of the backed-up data.

Beyond the capacity, connectivity and price – ?34,440 ($316/?172) – Sony is being circumspect about the Pocket Bit Pro’s specifications. Expect more to be revealed when the product ships in Japan in July.