I still have grayscale Handsome Squidward on my calculator. In fact it's pretty much frozen in time since high school aside from putting lots of calculus related stuff on it.
It's got a bunch of assembly source code on it for games I never finished and probably won't. One of them was gonna be a simple Sonic-inspired game, though who knows if that would have gone over well on an LCD that's slow enough that you can get grayscale like this.
