Wii64 is a port of the popular multi-OS N64 emulator, Mupen64, to the Nintendo Wii and Gamecube through the libOGC library. The emulator uses dynamic recompilation of the N64 machine code to PowerPC machine code and full hardware accelerated graphics to achieve (mostly) full speed emulation. Currently the emulator is in beta stage and can run many N64 ROMs at full speed in most cases.

emukidid and others still work on improving the emulator as the following video from 25th June 2015 shows.

https://gbatemp.net/threads/wii64-beta-1-2-wip-video.391632/