A U.S. patent has been discovered as filed by Sony in September 25th for a new PS2 or PS3 controller called the Control Docking Unit that will allow for the PSP to utilize a Plyastation controller. With the new slim PSP supporting a TV Out function, this new docking unit should go hand in hand with it and perhaps is a function of the rumble enabled SIXAXIS PS3 controller. The patent is available to view over here.

Control docking unit

Abstract

A control docking unit configured to accept a portable processing unit and provide alternate control operation of the portable processing unit. The control docking unit can be configured to position a display on the portable processing unit to facilitate use of one or more controls provided on the control docking unit. The control docking unit can position the display of the portable processing unit in a fixed or variable position. The controls from the docking unit can be coupled to the portable processing unit using an electrical, mechanical, or electromechanical interface. The electrical interface can be a wired or wireless communication link. The controls on the control docking unit can be configured to be substantially in the same configuration as a control unit for a similar fixed device. The portable processing unit can be configured to provide additional functions, features, or enhanced operation when coupled to the control docking unit.