I am a little bit of a redneck and like to keep a small pocket knife on my keychain because it comes in handy quite frequently. (Like removing the packaging to an electronic device. You know the annoying packaging that is hard to open with just your bare hands.)
Last month while I was at work I had a coworker freak out at me when I pulled out my keychain and he saw my tiny knife. He requested that I report my tool to the Supervisor of Quality Health Safety Environment to see if it is a company-approved tool used for cutting. It is not approved so I must keep it concealed. This coworker gave me the same response when he saw my steak knife in the lunch room.
I have found this similar reaction from coworkers at previous jobs as well. Here is a picture of my deadly weapon.