Speaking of emulators, my friend Mark periodically gets the urge to write emulators for hardware that came out when I was in diapers, or not born yet. (That's probably not his metric, but it's true anyway.) Last year he wrote a cool PDP-1 emulator that could run the original
Space War (1962) [scroll down].
Today he whipped up an emulator for the CHIP-8 virtual machine that ran on the COSMAC ELF (1976). His emulator has so many cycles to spare, he can easily dump PPM's to disk in the inner loop, which is
how he made the animated gif.
Insert obligatory "write a web server for it" comments here.