Nige has released CPCPSP for the PSP. It is a port of the Amstrad CPC emulator Caprice32. Release notes:

Without sound, about 92% of original CPC speed

With sound, about 75% of original CPC speed

Emulation of the 464, 664 or 6128

64/128k snapshot support

Very accurate emulation

http://nige.the-pub.org/cpcpsp/