I always carried a pocket knife around with me at work. They come in handy to pick stickers out of your hands, cut up an apple for lunch, pry out a jammed staple in a staple gun, cut stuff, etc.
Those little scissors in a Swiss Army knife are also very handy to have.
Working in the forest is a different kind of world. When someone asks to borrow your knife to cut their food, you first must say, "Be careful, it is razor sharp." and after they start cutting, you say something like, "Yup, the last thing I used that knife on was a dead skunk."