I use a camelbak mule, the old model. I took the bladder out and have a platypus in it's place, plus a prybar and other essentials. I have a camelbak trailblazer ordered, we'll see how that works. I like the narrow light profile of the mule, I think the trailblazer will be even better, I will have the new omega bladder, plus room for my other stuff. I think camelbaks are the perfect urban survial pak.