Anyone who used a Macintosh in the 80’s or 90’s remembers the Happy Mac icon – the smiling computer face that appeared on the screen while the machine was booting up. With my new ROM-inator flash memory kit for vintage compact Macs, hacking the Happy Mac icon is easy. The happy face is stored as a 20 byte raw bitmap, beginning at offset $FD2 (hex) in the ROM code file. It’s a 16 x 10 rectangle within the “screen” area of the surrounding Macintosh icon.

All of the icons above can be downloaded from the ROM-inator page. I went with the sunglasses for my Mac Plus, ’cause that’s how I roll…