i'm amazed that none of you have mentioned cranksets. if there is one thing and one thing only that you can do to your bike that will improve your climbing it's getting a stiffer crankset. still riding your oldschool square taper stamped crankset? try an xt, xtr, raceface cold forged, or any reputable company cold forged crankset, with an isis (or octilink) splined bb. you will instantly notice efficiency gains. drive train efficiency loss on climbs is high. when i installed my xt crank and xtr bb, i climbed my bike up a flight of 14 steps, effortlessly.as for the rider, obviously smaller gears help. try this for very, very steep, technical climbs: a wider, riser bar, keep your rists out and down, but stand, and push and pull the front of your bike up and over obstacles, as if you were bouncing up it on a pogo stick, while keeping cadence of course. if there are a lot of close obstacles and you need constant torque, try ratcheting your cranks. learning how to shift your body weight forward and backward is crucial.