Lots of people carry leatherman tools or hemastats for removing porcupine quills. I had the misfortune to see both in action last season.

My dog had over 100 quills in her face, tongue and throat. The trouble with those tools is that they require more effort and dexterity to open than they do to close. With quills, time is of the essence; you want to be able to pluck as fast as humanly possible.

After that incident, I went out and bought several sets of cheap ($3) spring-loaded, needlenose pliers. You simply squeeze, pull and relax your grip. I carry 3 pairs; one for me, one for my partner and one to turn up missing in an emergency.