Mupen64Plus - N64 emulator and plugins for Linux, Mac OSX, FreeBSD, and Windows
Project64 - Project64 is a Nintendo 64 emulator for the Windows platform.
1964 - 1964 is a Nintendo 64 emulator for Microsoft Windows, written in C and released as free software.
RetroArch - RetroArch is a frontend for emulators, game engines and media players.
CEN64 - CEN64 is a Nintendo 64 emulator.
Sixtyforce - Sixtyforce is an emulator that runs Nintendo 64 games.