If you're an owner of the excellent Turbo Chameleon 64 cartrige for the Commodore 64, you may already know that you can flash the firmware to emulate an Amiga 500 or 1200 w/AGA and turn your Commodore 64 into an Amiga.  One of the few hurdles is emulating an Amiga keyoard with the 64's limited keys.  This archive contains a short article on the keymappings along with images of the keyboard layout.  I also recommend viewing this YouTube video by Redrumloa that explains some of the most used key combos.  Additionally, Espen Skog has an excellent blog post on how to flash the correct firmware to your TC64.  Lastly, you can fin the minimig core and many others at the Retro Ramblings website.