Chapstick, car key, multitool[1], phone, flashlight[2], wallet
I plan for the worst when I step outside the front door. The number of times I’ve needed a light is twice the number of times I’ve needed a knife, but both are immensely useful to have even when going on quick trips.
I'm always baffled by people who say this. I always carry one and use it constantly from opening packages to working on servers, and I'll frequently have people come ask to borrow it when they need a screwdriver or bottle opened or something.