I hear the next expensive and unreliable product will be rubber bladders built into the frame tubes, with tiny hand-pumps (electric, for DI2 set-ups) and hoses which reach to the rider's mouth.

Water bottles aren't just uncool, they are un-aero. and the weight of bottles and cages? Outrageous. Trust me, before long all the cool kids will be riding bikes equipped with Tube-Sux® hydration systems. Options include the Little-Sucker® gel pump, and CO2 powered models ... because only a complete Dumbrowski would carry an uncool, an-aero, overweight hand pump.

If you can't fit it in your jersey pocket---stick it up your tube! Tube-Sux®, the original frame-contained hydration provider.