I have a Plaisir Platinum fountain pen that's awesome. It was pretty cheap as far as fountain pens go but it writes really nicely and has a good solid feel to it.
For day-to-day disposable pens I like the Zebra Sarasa ones, or the Pilot P500 for drawing. I bought a big box of the P500s to keep in reserve in case they ever stop making them lol.
Papermate inkjoy. The other nurses keep trying to steal my last one that I stole from my last workplace just before it started going downhill and stopped buying the nice pens. It was about 6-8 months before they swapped all our managers and supervisors with ones that were literally physically violent. Now that I think about it the pens have actually been a pretty good thermometer of all my past workplaces. If you go to a hospital and all the nurses have the same decently nice pens, that means their employer is probably taking decent care of them (at least as far as healthcare execs go) and well kept nurses are better at taking care of patients.
The cheap white plastic bics with the colored rubber grips are some of the most consistent pens ever. The cheap black/blue all plastic ones are some of the shittiest pens ever. I don't understand how this is the case.
I'm no pen enthusiast, but I used to really enjoy Zebra. Build quality was good for the price point, and they were super smooth to write with. Unfortunately the quality went downhill maybe 5 or so years ago and they haven't been great in my opinion ever since. They still feel fine physically, but the ink will stop dispensing randomly while writing. Got sick of it and switched to Pilot. Been using Pilot Precise V5 0.5mm and find them great. The ink runs a little wet though, so the only downside is that if you rub your palm across the page too soon after writing it'll smear a bit.
Parker, specifically the Jotter. I still have and use a stainless steel one that I bought in 1999 because I kept losing pens, and I thought that if I spent a little more on one I might take better care of it. It's my favorite by far.
I’m a big fan of the Tactile Turn machined pens. They are made in titanium, copper, and bronze, and they have microgrooves for grip. They make bolt and click pens in standard and slim width. They take either Pilot G2 refills, Parker-style refills, or (in the case of the mini) Pilot G2 mini refills.
Seriously, I’ve never lost one in the years that I’ve carried them. And the writing experience is drastically different than writing with a cheap plastic one.
I carry a Fisher Space Pen everywhere, but I switched its cartridge for Pilot Hi-Tec-C refills. It takes a little fiddling to get the refill in there, but once it's in it works great!
Pilot Hi-Tec-C is a gel pen with refills that happen to fit in the Space Pen. It puts down a crisp, fine line.
The problem with the stock Space Pen is that it's a messy ballpoint. I might be getting worse-than-typical results due to being left handed, but in general I find ballpoints don't write crisp lines, and the ink smudges on my hand much more than gel pens do. But with the gel swap I do lose the feature of being able to write upside-down.
Zebra F-402 - I write really small and their fine tips flow great but don't run. Plus they're cheap enough that I don't care when my wife or kids steal them out of my desk.
The ability to use home-made inks, guache, and stick-inks makes Ackerman very special. Particularly since I get to use my favorite Brause Bandzug nibs. And of course there's the fact that they're a small specialty company helps make them "favorite".
If you're asking who makes my favorite pens for every day carry or low-maintenance with standard fountain pen inks, definitely Lamy. They will still stand out a bit in a business setting in a way that might be a bit uncomfortable for some, but not in the brute utilitarian way Ackerman's do. I love broad nibs, and frankenpens just aren't reliable enough for me at work.
Back when I constantly needed a pen I used to use a Parker espirit telescopic fountain pen, since it was the best small fountain pen that cost little enough that I wouldn't mind loosing, but it was still small enough and good enough for my tastes. More recently since I stopped needing an actual pen with any sort of frequency it just kept getting dry and I just decided to stop carrying one.
This days the only thing that I physically write with any sort of frequency are ttrpg character sheets and for those I just need a good pencil, so I moved to the wsd magnetic 2.0 mm lead holder. I just love it both as a great mechanical pencil and a fidget toy
Cheap enough that if it breaks or you lose it or some such, you won't be that upset, but writes wonderfully. It is nice to have a pen where you can choose your own ink, and it will accept either refillable cartridges or pre-filled cartridges.
The way the cap posts on the back of the pen is pretty unique as well.