I own what you might describe as "a lot" of pocket knives. Not as many as real diehard collectors, no. But, conservatively, about three or four time as many as the average person. Almost all of them were acquired for a theoretical purpose. My Opinel No. 8 is a "desk knife." My Boker Plus Urban Trapper is a "dress knife." And my Spyderco Dragonfly 2 G10 is ostensibly the all-important EDC. But the "knife" I use the most isn't actually a knife at all. And I think that's what makes it so useful.
The Shard is what Gerber calls this little keychain multitool, and theoretically it has seven functions. In my experience, it really has about three. First is the bottle opener, always nice to have on hand. And then there's the mediocre-but-always-handy Philips head screwdriver. Then, on the business end, is a combination wire stripper/puller, flathead driver and pry bar. Or, for most of my purposes, the knife-ish bit.
What I've realized after years of poring over different types of steel and sharpening edges to the point of shaving hair is that most of my everyday "knife" tasks barely require what you might call a "blade," much less a particularly sharp one. Breaking down cardboard boxes, ripping through plastic wrapping, scraping things off of other things: these are all jobs a sharp knife can accomplish, but are also quite suited to fairly blunt edge.
A knife that's dull enough to be unwieldy but sharp enough to be dangerous (not to mention potentially illegal, depending where you live) is actually the worst of both worlds and, let's be real, the space a pocket knife is quite likely to inhabit most of the time. And for me, a pocket-safe keychain is a much simpler tool to maintain than a sharp knife. Not to mention one I don't have to remember to leave at home when I'm going to the airport.
Sure, there are cutting jobs in my life that only a real knife can accomplish. For me, virtually all of them are in the kitchen. And cutting food with a working pocket knife, while very tempting, is also gross. Maybe things are different for you; I might be singing a different tune if my day-to-day life saw me cutting a great deal of sizable rope, for instance. But on the rare occasion a bigger cutting job presents itself, I can usually spare the time to find a bigger knife. Even then, I have found that a vigorous scraping with the Shard's wire stripper can annihilate most small twine and string in a pinch.
If I could go back in time and not buy all these knives that I have, and instead just have the Shard, is that the path I'd take? No way! A few of my real blades (the Opinel and Dragonfly in particular) get their fair share of use. Would I buy, maybe, half as many knives as I currently have and be just as happy and a few hundred dollars richer? Absolutely.
At the going rate of under $10, the Shard is an easy impulse buy that I heartily recommend. That is, if you can stomach the retroactive buyer's remorse of using it more than your actual knives.