I think you鈥檙e after two different things here, John. Maybe three. For a triathlon, I wouldn鈥檛 think you鈥檇 want anything more than a lightweight, compact hydration pack鈥攕omething such as 鈥檚 Rogue Hydration Pack ($58). It鈥檚 just big enough to hold two liters of fluid, plus a few energy gels or arm warmers. And its streamlined shape is ideal for cycling. But really, unless you鈥檙e doing something more than Olympic distance (40-kilometer ride), I鈥檇 get by with bottles. I just don鈥檛 think a pack is necessary.
The Rogue
The RogueBesides, for snowboarding or camping you鈥檇 need a much bigger back than would be remotely useful on a bicycle. For that, you鈥檇 need something such as the Blade pack ($135). It鈥檚 purpose-built for snow sports, and can carry a snowboard or a pair of skis. Plus it holds tools such as shovels, poles, and extra food or clothing. It has 1,800 cubic inches of capacity, which qualifies as a mid-sized daypack. Too big to put on your back and take biking鈥攊t weighs four pounds, for one thing. Plus it鈥檚 fairly bulky and non-aero. 鈥檚 Quiver pack ($65) is a little smaller (1,500 cubic inches), holds skis or snowboards, and has a little more 鈥渦rban鈥 look than the Dakine.
By 鈥渃amping,鈥 do you mean 鈥渂ackpacking?鈥 If so, then that is a third kind of pack. Here鈥檚 you鈥檙e looking at something such as the Aether 85 ($289), a full-featured backpack that can handle loads for close to a week of hiking. Or, for a good day-hiking pack, go for something such as the Lookout 40 ($90), a comfortable, nicely detailed daypack with lots of pockets for organizing stuff and enough capacity (2,440 cubic inches) to take a full day鈥檚 worth of gear.