Nestopia is an open source NES/Famicom emulator designed to emulate the NES hardware as accurately as possible. Nestopia emulates the NES CPU at cycle-exact granularity, ensuring full support for software that does mid-scanline and other timing trickery. Nestopia has been ported to Pandora by StreaK; for fullspeed emulation you need to overclock your Pandora to 800mhz.

Features:

Famicom Disk System support
VS. UniSystem support
NSF support
Accurate video emulation, including artifacts of the NES’s NTSC color encoder
Savestate support
“Rewind” support
IPS patching support
Movie recording
Several non-standard controllers and peripherals
Support for over 200 memory mappers
Cheat code menu with built in Game Genie
ZIP/RAR/7zip archive support

http://repo.openpandora.org/?page=detail&app=nestopia-app