Ask any G.I. what the (U.S.) army's best invention is, and (s)he'll probably tell you "the P-38". No, not the airplane, the can opener. If you've been in the army, you know the thing I'm talking about. Invented in 1942, the P-38 is a tiny piece of steel, about an inch and a half (3cm) long, originally issued to open c-ration cans. Once ubiquitous, they became harder to come by after c-rations were phased out in favor of MRE's, but somehow, everyone I knew had one, and no one would part with it willingly.
The tool got its name, allegedly, from the 38 punctures it takes to open a c-ration can with it (it is also nicknamed the "John Wayne". It is the most reliable piece of equipment ever issued; weapons jam, vehicles break down, but the P-38 will never break, bend or rust, it requires absolutely no maintenance, and its "MacGyver" factor is not to be underestimated. Besides opening cans it has been used, among other things, as a screwdriver, a fingernail cleaner, and a makeshift knife. It's hard to explain the feelings inspired by this five cent piece of steel but, for a lot of guys, these things hold the same kind of sentimental value as their dog tags and medals after they get out of the service. I've seen more than one grown man in a panic after misplacing his. Mine hasn't been off my key ring in 11 years, and I still use it sometimes, in a pinch, to open cans. It also works great for zipping through packing tape and shrink-wrap. I know that if I lost it, it could be replaced for about fifty cents, but it wouldn't be the same, so I keep a pretty close eye on it. | 
