(After some thought I put this in the Acoustic forum rather than elsewhere because I'm mainly interested in what other acoustic players use. Not that the electric or archtop folks don't matter, but their requirements are going to be different.)
So, guys. Picks.
There are about eleventy thousand different choices, and yet we each seem to find our favorites. I've known players who have crazy expensive picks, tending towards being super thick, and I've also known players who are fine with basic Fender medium faux-tortoise or plain Dunlop Tortex. I even met one guy online who strongly favors picks made from old credit cards with a Pick Punch, and I refrained from suggesting a psychological evaluation; whatever works for him.
So what's your preference? And why?
Myself, I favor these Cool Picks ultra, in medium gauge:
They're made of something that Cool amusingly calls "cellulon bi-matrix," which sounds like a mouthful of techno-bull, but it is a very unusual material. If you drop one on a hard surface, it sounds like glass. And they really do have a tone all their own, bright and crisp. I like them for the tone, for the rubberized grip, and for having very pointy points. What I don't like as much about them is their price (usually about a buck apiece) and their longevity, which is pretty short. These are the only picks you will consistently wear out before losing them, because they're not really intended for the kind of wear acoustic strings put on them.