You know, if you wanted to implement a Canon Cat, you could probably do it pretty easily and on a reasonable budget with a modern 16-bit or 32-bit microcontroller, an SRAM chip, an SD card, an LCD, the keyboard of your choice, and Lua instead of Forth. Or you could hack up Emacs or something to support LEAP keys and whatnot (maybe you can relabel the Windows key on your keyboard), although that wouldn't give you the instant-turn-on ability. Most of the detailed specs were available on the web for a while under the name "The Humane Environment".