I lost my first Leatherman on the way back from France--forgot to pack it in my checked luggage, and didn't realize it until I was almost to the gate. I forget how many times I had flown with that little orange tool while I was on the forensics team at GMU, which made it all the more galling to lose it to airport security.
I bought the Leatherman in the first place to replace the pocketknife I carried. I had a knife because it's a handy thing to have, and because I wanted to be Macgyver when I grew up. But the knife kind of freaked people out--it was a four-inch flick blade, and I enjoyed the snap of the wrist required to open it maybe a bit too much. It made people think I was some sort of psycho cannibal survival fetishist, when in real life I could no more survive in the open wild than I could flap my arms and fly.
The Leatherman was a lot less threatening, since it's basically a pair of pliers mated with a Swiss army knife. No-one is threatened by a Swiss army knife or a pair of pliers. Besides, I was sick of trying to use the pocketknife as an impromptu screwdriver. It's possible, and it feels very resourceful the first time, and then after that you just feel like an idiot.
When I lost the first tool to the Charles de Gaulle security team, I went to Price Club and bought one of their bubble-wrapped packages with one of the original Super Tools. The Super Tool is basically the worst of both worlds between a pocketknife and the smaller Leatherman I'd been using before. It is a hefty chunk of stamped stainless steel, which immediately began tearing holes in the pockets of every pair of pants I own. The knife on it is large enough to scare passersby again, but it's located inside the handle of the pliers, which means that it takes five minutes just to get it (or any of the other blades/files/screwdrivers) out. And then once you have any of the blades/files/screwdrivers out, they're locked into place with a hellishly-resilient leaf-spring release, so it won't close on you (which is nice) but it'll flay the skin off your thumb while you try to put it back.
So I'd finally had enough, and this weekend Amazon shipped me another Leatherman Juice like I'd had before, relegating the larger version to my messenger bag, where I will hopefully never need it again. Some people might wonder if I needed either one in the first place. But I tend to find that the moment I don't have a pocketknife of some kind handy, I tend to need one. Even just here at the office, there's always packages that need to be opened, or equipment that someone would like to have rackmounted, or a tape that's broken and needs to be rewound. Yeah, I'm sure I could find a screwdriver or improvise something eventually, but why bother? Besides, coworkers appreciate having someone handy around.
Also, I still have dreams that I'll be trapped in the hold of a falling airplane, or need to defuse a bomb using only toothpicks and a bag of M&Ms. I never actually watched a lot of Macgyver as a kid, but the idea of it really stuck with me--plus, I was reading a lot of Heinlein at the time, and the creepy libertarianism didn't take but the jack-of-all-trades competency worship did. Nobody likes to be in a situation where they feel helpless. Maybe carrying a Leatherman or a pocketknife is just a psychological tool for maintaining some kind of control. Maybe it's a symbol of wanting to be able to fix things and solve problems. Or maybe I've just gotten used to it after so many years, and it's force of habit.
In any case, if you're like me, you may enjoy Wikipedia's List of Macgyverisms, including icons showing whether a problem was chemical, optical, physical, or explosives-related. I'm not really threatened by violence in the media, but it is nice to read a set of plot synopses for a show that explicitly rejected violence and guns in favor of invention and loosely-sourced scientific knowledge.