You want a daypack, need a netbook backpack and fancy a hydration pack. Three different Crumplers is one option. The three-in-one Yee Ross is the other. As flexible as a Romanian gymnast and almost as tall, the compact Yee Ross holds a 4-litre hydration bladder or netbook in a rear sleeve, your tunes in a centre zippered pocket and your stuff-du-jour in a 13-litre general cargo space at the front. It also has dual external zippered side pockets for those things you want to keep close at hand. Small but perfectly thought out, the Yee Ross' padded shoulder straps integrate hydration tube and audio slide through and combine with centre and detachable waist straps for ergonomic carrying. This Swiss army knife of backpacks is also built to last, combining a 900D outer and Air Mesh padded spine with 150D Rip-stop lining.