I’ve carried, on my keychain, a little penknife. Mini-“Swiss Army” style, a Directech give-away. A little 1.5″ blade, a matching fingernail file, little scissors, little tweazers. It’s come in remarkably handy any number of times in cutting threads, opening boxes, etc.
Off the key chain. I may have to travel by air, and I know that I’ll forget about it, and end up turning it over (assuming I’m not locked in a room somewhere for a while).
Sheesh.
But, y’know … I can’t complain about it too much.