I was playing Angband on my laptop during a fight (amazing how many hours you get out of a machine not running a GUI) when the passenger next to me called out that I was trying to hack the plane. Was fun having to calm everyone down by basically teaching the stewards how to play Angband.
Oh god, I've been here with idiots. Such as people thinking that my The Sims game was me spying on people or that the marzipan's answering machine cartoons on homestarrunner.com where me leaving prank calls on actual people's voicemail.
The technologically illiterate drive me crazy, I can't tell you how many times I heard "Don't install firefox it messes everything up"
Eventually I "fixed" everything, that Firefox broke by just deleting the shortcut to Internet Explorer, putting up another shortcut to firefox, and giving it the Internet Explorer icon and name. People thanked me for owning up to my mistakes after that.
Thankfully this was back in the early 2000s where computers were just hacker Magic from the movies. I don't think anyone is the stupid today unless they're in Congress