There's nothing cool about mine. I have two cages and I replace the standard bike bottles with scavenged one-liter soda bottles, one of which has a squirt top. More volume, less weight that way. For touring, I add one 2+ liter platypus bladder to each of my two panniers and fill as needed. If six+ liters isn't enough (it always has been), I could take another platy--they only weigh just over an ounce each. I always have room in my panniers for the volume. On day rides, the two liter bottles have always been enough if I start hydrated and get to water at the end of my ride, or have a place to refill mid-ride. I live and cycle in Arizona.