Reader Florian submitted a self described "No Tech beverage cooler." This is the email we received:
Just keep the sponge wet while you ride and the evaporation moisture from your bottle contents will help provide you with an nice chilled drink anytime and anywhere. It works great even during the hottest days.
This made me think of a previous hack focused on keeping water from freezing that could possibly be used to instead keep water cold. The hack below is meant to keep cold wind away from the bottle in the winter, but if you filled the space between the two bottles with ice or perhaps an ice pack you would have a little cooler.