A real effort is being made to bring a Jaguar emulator to the PSP. In fact, I believe that Virtual Jaguar will be the first Jaguar emulator of any kind on any console. You can find out more specifics (along with installation instructions) over at the Virtual Jaguar website. The initial version is a bit on the slow side, so it'll be interesting in hearing how the developers have handled all of the button-mapping issues as the Jaguar controller still holds the record for most console controller buttons ever.