A:Well, quite a few. What youre after is simply a large, comfortable backpack, one that can carry a load well and that stays close to your body for balance.
The decision largely depends on your budget. If its a bit tight, REIs Flash 65 packs an amazing amount of features into a $149 pack. Its the size you want, has pre-curved hip belt and shoulder straps for a good fit, and can be stripped down to a "light" configuration if youre trying to save pounds (maybe on a side trip). Two aluminum stays and a plastic framesheet help distribute the load. And it has lots of places for hydration bladders, gloves, wet clothes, and the like. Pretty impressive.
Next up the ladder, the Gregory Baltoro 70 ($289) is a little larger and has features such as a sleeping bag compartment. Gregory is well-known for the great suspensions in its packs, and it would carry beautifully while youre skiing. Ospreys Aether 70 ($259) is in a similar price range, same size, and similar packing configuration. If this is your sweet spot, maybe try on both to see what fits best. Ive been wearing Osprey packs the past few years and like them very much. But Gregorys packs always have been good to me, as well.
Highest end, Arc'teryxs Bora 80 ($375) is a little larger still (but not too bigon a long trip youll have a largish load). Beautiful design, top- and side-loading, great packing features for organizing gear, and lots more. And very tough. ArcTeryxs packs are works of art, the construction is so good.
So there you go. A pack for every budget.