Living in a big city I think it's kind of frowned upon if I were to carry my knife around with me.

But whenever I'm in the country or camping I have 2 knives with me. Both are kabar military knives. One is a full length USMC knife(7 inch blade overall 12 inches) And the other is a short blade version of it(5 inch blade overall 9 inches)

I also take this short kabar with me when I go snorkeling or out on the water since the sheath and blade handle are made out of a plastic and won't rust.