We're digging the Vapur, a refillable and flexible water bottle that can be neatly folded, rolled up or flattened when the agua's gone (or before you load it up at a water fountain). It's easy to carry around and sort of like a Murphy Bed--it's only in its bulkiest form when it's in use, and the rest of the time it pretty much disappears.
Says the company,
We have set out to make tap water infinitely portable, universally available and ethically sustainable.
Water is the source of all life. It is not a commodity to be bought and sold for profit.
The BPA-free bottle will hold 16 ounces, and it can also be frozen for use as an ice pack.