GnGeo: An open source emulator for GP2X and Linux.
NeoCD/SDL: An open source emulator for BeOS, Linux, and Windows using SDL.
NeoPocott: Freeware Neo Geo Pocket emulator for Acorn RISC OS, BeOS/x86, Dreamcast, DOS, Linux/i386, Linux/SDL/i386, MacOS, PocketPC ARM & MIPS, Win32, Win32/SDL.
NeoPop: An open source Neo Geo Pocket emulator for Windows.
Rage Homepage: Home of NeoRage a fast Neo Geo emulator, also of the discontinued Rage emulator.