I carry three knives also, must be an airborne thing.

SAK, usually the ranger, sometimes others.

Sheath knife, my venerable Gerber Command I, or issue survival knife. Could be my new Mora now.

Multi-tool, usually some form of Leatherman.

Can't tell you how many times I've use a knife to cut, poke a hole, start a fire, perform minor surgery, open a can, whatever...

If I had to beat feet with literally seconds to spare, the first thing I would grab is a knife, followed by a lighter and a flashlight. From there I can MacGuyver the rest.