Sony filed an application with the US Patent Office for a "control docking unit" which would connect a PSP to the PS3's SIXAXIS controller.
Patent application 20070174531 proposes a link between the two devices, allowing the controller connected to the PSP to control the system. A "wired or wireless communication link" could be used, suggesting that both PS2 and PS3 controllers could be used.
While many patents never make it to the marketplace, this is an interesting development nonetheless.
Author: Philip Morton
Source: http://thunderboltgames.com/
Source: Sony reveals plans for PSP and PS3 controller link
