A number of folks have suggested the Buck Vantage Pro. I have to say from my experience this is an excellent general use knife done in a top drawer steel. The pocket clip is tail mounted so that the knife itself is almost completely unexposed. Pocket clip can be reversed for carry on the other side. There are three different ways to open the knife with one hand: 1) flipper tab, for a flip-n-snap one-handed open -- very fast, 2) the thumb hole, for a more "civilian friendly" one-handed open that doesn't startle onlookers, and 3) the thumb-n-forefinger pinch of the thumb hole, flipping the handle down.
The blade is a high grind, which makes it kitchen friendly (you can slice food and it doesn't act like a splitting wedge, tossing food off the counter). It's happy doing tomatoes. I've made salads with mine. Does fine with salami and cheese.
It's also sharp out of the box, and with just a little attention to dressing & polishing the edge, it becomes hazard-sharp.
It will do a day's work without complaining.
I'm a fan of the Vantage Avid, but that's just me liking the Sandvik steel. If you cut a lot of cardboard, the S30V will wear better.
If you're using this in a utility setting, a long blade isn't going to help and will, in fact, be more clumsy. Something between three and four inches should work fine.
I don't recall if I saw any recommendations for the Kershaw Needs Work in the thread so far, but in a utility environment, this is a serious working blade. It's an assisted opener, has pocket clip. It's bigger than it looks; Wharncliffe blades can be like that.
Frankly, if I were going to be in a back-room utility cutting environment, and I knew that I'd be cutting a bunch of cardboard, I would carry a second knife.
For your scenario I might, for example, carry something like a Vantage for general use and something like the CRKT Edgie 2 self-sharpening knife for box cutting and such. I have some of the original Edgie knives. The first version was a sheepsfoot blade, sharpened with a sort of one-sided chisel grind, and it sharpened itself every time you closed it. I don't think the first one had a lock. The new design is symmetrically ground and has a backlock. It's a Wharncliffe blade, so you have a usable point for penetrating packaging when needed.
I could get a Vantage Avid and an Edgie 2 and probably stay under $80. If carrying a second knife is a bad idea for you, then disregard that part.
I saw some Spyderco suggestions. Spyderco is quality that needs no apology. Something like a Manix 2 would be all the knife you'd need in a work environment. Seriously, take some time to look at the Spyderco stuff.
It's too bad you can't carry a fixed blade, 'cuz there's a few Mora offerings I'd suggest. Those knives are real users.
In general, I wouldn't get a really large knife. Hard use doesn't imply size. You need excellent control of your blade, and the longer the blade is, the more control you have to impose.
Hope some of this is useful.
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