I carry a spyderco rescue, have for 15 years, old one with the plastic pocket clip, so I don't scratch vehicles when squeezing by them. Blunt tip, cutting seat belts off of people and fully serrated blade, for work that is the best as it cuts everything from fuel line to wiring harnesses.
The other is a cold steel voyager, 5" pocket sword, non serrated, honed to a razors edge, it never gets used for work purposes, its more of a social tool

As far as sharpening, at home I use a belt sander with 1000 grit paper and sand away from the edge, sand until you raise a burr on one side and flip it over and break the burr. In the field I carry a Kershaw, 2 piece diamond stick, light weight and does serrated blades as well. The stick looks kind of like a tongue depressor. I have the cardboard wheels for the grinder motor and it does a really good job too, but the belt sander rules. That's what knife makers use.