I remember spending way too long figuring out the very first puzzle in the old text based adventure game that had me stuck in the dark. All you have to do is open your fucking eyes.
I never figured out how to manage to grab the electronic thumb that Ford was carrying to get off the planet.
I did find out that "Fuck" was programmed in as a command. I got frustrated and typed "Fuck Ford." The game spat back "This is a family entertainment game, not a video nasty."