Vern... Rick already posted a pic in my post titled "Zippos".
Rick... funny you should mention the military. I was a grunt in the US Army. On night ops we used to use Zippos for signaling in the dark. Not by actually lighting them, though we did do that sometimes, it was the distinctive sound a Zippo makes when the lid is opened and closed. It's the only lighter that sounds like that, so if you heard it in the dark you knew it was an American out there in the bush. Also, overseas, at least in the orient, local artisans would use small hammers and chisels to etch all sorts of things onto Zippos, i.e., unit crests, eagles, dragons, etc. Their work was quite good. I had several of these at one time but, alas, they've disappeared over the years. "Liberated" by friends no doubt.
Again, thanks Rick.