Almost all the time, I wear cargo pants because I want pockets.
On my keychain, I have a simple tool for poking reset buttons that are inside small access holes; I made it from a paperclip. I also have a SwissTech folding pliers tool, which I mostly use for its screwdrivers.
I also try to never be without a paper towel or at least napkin in a pocket. If someone spills coffee or something I have the fastest response time, and sometimes I want to dry my hands in a bathroom that is out of towels.
I carry a Swiss Army knife, one that isn't as thick as my forearm so it doesn't have pliers or a saw. It does have both scissors and a corkscrew. I used to carry one with a Phillips screwdriver, but the SwissTech on my keychain covers that now, and once when someone really needed a corkscrew I didn't have one. Never again! Not on my watch!
(By the way, I have always wished that the Swiss Army knife companies would make a "companion" tool, that doesn't have the basic knife blades and screwdrivers but has the saw, the file, and the other more exotic tools. I'd sooner carry two slim tools than one thing as thick as my forearm.)
I carry a Fenix E11 pocket flashlight. It runs for many hours on a single AA cell, with plenty of light, and it has a high-power mode. It claims 8 hours for the 35 Lumens mode, and less than 2 hours for the 100 Lumens mode. I haven't verified those numbers. I love this thing: it uses a Cree LED to produce a really bright white light. It's 21st Century technology; nobody could make such a thing in the 20th Century.
I carry a Spyderco "Delica" folding knife. It's just the thing for opening packages from Amazon or whatever. It locks open for safety, and I love the thumb hole for one-handed opening. (I'm amazed that they were able to patent that. Once that patent expires I reckon most lock-back knives will have a thumb hole for opening.)
I also carry a Spyderco "Rescue Jr." folding knife. It's specifically designed for tasks like cutting a seat belt when rescuing someone from a crashed car. I've never needed it for this purpose, so its other purpose is that I keep it clean, and if someone needs a clean and sharp knife for food, I offer that one. The Delica usually has little slivers of packing tape or other crud on it from opening delivery boxes.
I carry an "unbreakable" pocket comb. Not only do I use it to comb my hair, but I usually use it to prop a door open when I want to make sure the door doesn't lock closed behind me.
I carry a Fisher "space pen" in black ink, and a cheap disposable pen in blue ink. I can easily tell which is which, and if someone wants to borrow a pen I usually loan them the cheap one and don't get upset if I don't get it back. (If I loan the Fisher, I keep the cap; this reminds people that they need to give it back.)
I carry enough cash for cab fare or a meal, buried in my wallet. I try never to use this as I want it to be there if I ever need it.
I also have a backpack that has a whole bunch of stuff in it (USB charger and USB cables kit, mini first aid kit, etc.) but the above is what I carry all the time.