Tons of PSP emulation happening .. maybe NGEmu should open a new PSP section.
Some of the highlights ..
RIN (Gameboy/Gameboy Color emulator) and two other unofficial builds of RIN floating around. There is also a SNES emulator in the works and a video of it in action out. InfoNES has been ported over .. and a PSP emulator called PSPE in the works .. well sort of. It is a PSP elf interpreter that plays some of the techinical demos that are out. This is how emulators are started so you never know what may come of it over time.
Most of this stuff can be found on PSP Hacker .. http://www.psphacker.com