I never carry one on me in an urban setting. A phillips screwdriver is consistently much more helpful in the urban jungle. In the woods I use a quality multitool.

My busker friend had a big scary knife and the cops came around. They talked to him and it was fine but it may have cost him some money as a busker by getting fewer coins.

I'd suggest keeping your knife out of sight.

I follow Gibbs rules, carry Kershaw's Zero Tolerance 0350 currently (black, plain edge). It's big (wide blade/handle) and heavy and a pain to sharpen ('S' shaped blade) so I'll probably get a new one sooner or later.

I think the reason more people don't carry "such an amazingly useful tool" is because they aren't allowed to or don't want to give others the wrong impression. I'm sure we've all gotten the weird looks when we've pulled out our knives to open a package or something. Plus there are all kinds of places that have zero tolerance for weapons, job sites, offices, government buildings, etc. Most job sites that require you to complete a task, like opening boxes, cutting wires and tie downs, etc, will supply you with the tools to do so in an efficient manner, making your pocket knife useless.

As for gaining female market share. I think the problem is that the things knives are useful for, aren't what the ladies are doing. Statistically speaking. Most women I've known carry a knife in their cars glove box but only a couple have carried one on their person and they were always the ones that were into the activities that weren't "stereotypically" feminine. I think if they (females) have a lifestyle where a knife is useful, they'll carry one. There probably isn't some magic "make it pink and shiny and slap a kitty logo on it" formula that will pull all the girls into the store.

I've carried a pocket knife for more then 58 years, and can't see any reason to be without my pocket tool. Its used several times a day often, and is simply a part of me. I have built several of my own design while in the navy as a machinist, and appreciate the usefulness and easy access. A pocket knife is capable of many uses, and the better steels can give you a blade that will give a long practical life. My favorite right now is my Cold Steel AK-47 knife, and a smaller two bladed Barlow style for everything from cleaning finger nails to cutting and even acting as a wood scraper. The larger AK is for quick one handed cutting where I don't have two hands to open a conventional knife, or where the bigger blade is need for heavy cutting. Keep us informed on your ideas for a knife, I'd like to see what you come up with. Designing a knife is fun and really gives you the chance to apply your ideas in a very personal tool. I had several hex holes milled into the slab sides of my custom knives for use as small handy wrenches, and a serious idea would be to mill the sides of the standard screw drivers parallel like a quality gunsmith screw driver so they don't cam out of the screw holes and mar stuff like the cheaply made stuff does with their tapered faces. (I did that with the swiss army knife in my tool box and its a treat to use it) Might be fun to ask the readers here what they would want in a knife and see what features might interest them.

I carry a Leatherman Wave. Any time that I'm out climbing or at work. Never when I go out in the evenings though.

I have had a pocket knife on my person since I was 12. I have always thought of it as a tool and even during a mugging, did not think of it in any way as a weapon.
Now, I am looked down upon if I carry my tool, to certain places.
My Dad gave me the pocket knife (long before the 'multi-tools became popular, other then the Swiss Army knife), it had a useful can opener, bottle opener, and leather punch, besides the two blades, and it got me out of a lot of "car" troubles.

It was a BARLOW, with hardened (not stainless) steel blades and so needed to be cared for. It rarely needed sharpening however and held a good edge if properly used. I still have it and it was 41 years ago that it was given to me.

I always carry a knife on me, they can be really useful.

I frequently carry a multi-tool. In fact, I carry two in a belt-pouch.

However, I no longer carry them at work, since they allegedly worry the students.

_{They aren't worried about the bunsen burners, acids, radioactive samples, chisels, hacksaws, pillar drills, laser-cutter and disc-sanders, lathes and band-saws, but they are worried when I sharpen a pencil with a one-inch blade, but there you go...}

I think you need to fine tune your question depending on what you want to get out of it. What do you consider a pocket knife, a utility tool or a weapon? How big and do kids get them? Yeah, a multitool or pocketknife is handy on many occasions but I do not want to worry that everyone is carrying a concealed weapon around. Greetings from NYC.