I got to hold one of these:
That's the Smith & Wesson .500 Magnum revolver. It fires a bullet that's a half-inch in diameter and travels at more than 1600 feet per second, and the gun itself weighs about six pounds empty. It is expensive, impractical, and wholly delightful, and my friend's sister Julie owns one. I found this out quite by accident: we were chatting about the calibers we could use when we went shooting, and she mentioned a .50 caliber handgun. I casually asked if that referred to the Smith model in question, and she said it did, and I expressed great interest (i.e., slobber), and she mentioned that she happened to have it right in the back of her truck...
Julie is a very nice woman. Also, dangerous.
She's promised to let me shoot it when we reschedule, and I promise a full report.
(And for those who may be inclined to wonder about the whole phallic thing: really, it's not true. The sad, pitiful truth is that the gun nut's automatic reaction is, "Ooh, TOY!")