They keep this 20+ year old laptop around because it has a serial port and every now and then that comes in handy.
You can’t really see it in the picture but the laptop is pretty thick and heavy.
PCIe can indeed be your friend! I got one with parallel port and no device to connect to. Currently looking for ideas.
The parallel port used to be used for connecting all kinds of homemade devices like logic analyzers, microcontroller programmers, frame grabbers, or just used for GPIO for reading switches and controlling relays. It was a lot easier to access directly from DOS than it is from Linux or newer versions of windows though.
Of course you could just connect a printer to it. I’ve got a thermal receipt printer that I’ve been meaning to write software for eventually. It will print out whatever I cat to /dev/lp0, but I can’t easily do any formatting or control the cutter that way.
