I’ve heard tale of epic thrift-store gear-scores—barely used Patagonia shells or cozy jackets from The North Face—but these big brand-name finds are extremely rare. Keep an eye out for them, for sure, but also consider the following:
The Gear Guy's favorite funky fleece.
You likely won't find a second-hand hat that wicks moisture or breathes incredibly well, but you will find one that offers the main utility of a hat: keeping the sun off your face. Bonus: you might stumble across one that shows your flair like the Party Animal cap I scored in Lake Havasu City, Arizona.
Most people discard a Coleman stove the first time it breaks. But these portable gas cookers are not terribly difficult to fix; once you become familiar with maintenance you can have one of these car camping staples forever.
No matter how ugly and featureless a fleece is, it will still manage moister well. The synthetic material will also keep you insulated by trapping dead air under a shell.
Nylon Running Pants
Gore-Tex might be hard to come by, but regular ol' nylon running pants are good in a pinch, especially for wearing over fancier mountaineering pants. Nylon pants, which are normally pretty water- and wind-resistant, can protect other layers while you glacade.
Synthetic fibers are good for moisture control; polyester-blend shirts have essentially become uniforms for raft guides because they dry quickly--and block the sun. Some of these shirts get better with age; the more threadbare they become, the better they breathe.
Although a wool sweater will likely scratch considerably more than a fancy new merino layer, any top that is 100 percent wool will provide superior water regulation, smell mitigation, and warmth.