My first thought was my Leatherman also but on reflection I would have to say my Woolrich wool shirt. It's a heavyweight wool that they don't make anymore. That thing has kept me warm on more hunts than I can remember. It's tough too! I've worn it for most of my deer and turkey hunting for twenty years! Mind you I'm careful when I wash it and just hang it to dry. If they started making them again I would honestly pay $100 for one. TC