A newly surfaced patent that was apparently filed back in September  of 2005 seems to suggest that Sony is (or, at one point, perhaps was) pottering away to create a controller dock for the PlayStation Portable, allowing players to control games on the hardware with either a PlayStation 2 Dual Shock or PlayStation 3 SIXAXIS pad.

Although the design doesn't do anything for the PSP's portability or its sleek and stylish design, it could well eradicate a lot of complaints by users about the awkward placement of buttons on the machine and, most crucially, the lack of dual analogue sticks.

However, thinking of it in terms of being able to plug the upcoming, slim-line PSP into a television for big screen gaming, the prospect for the add-on becomes a lot more attractive – if again defeating the object of the PSP as a handheld travel companion.

Submitted to the United States Patent and Trademark Office, today's news partners another PSP design rumour that hints a PSP with a twisting screen may also be in the pipeline.

(Editor's note: a PSP dock is all-but worthless from an ease-of-control point of view when users can simply take advantage of Nyko's truly excellent Charger Grip, which virtually turns the PSP 'into' a PS2 controller, is retractable, and adds an extra 5 hours of operation too.)