Tempra Technology has a can that chills itself:
The Instant Cool Can (I.C. Can™) is a 100% safe and environmentally friendly self-refridgerating[sic] process that cools using brilliantly simple water evaporation. In fact, it's proven to lower beverage temperature by a minimum of 30° F (16.7° C) in just three minutes.
From the cutaway shown below, it looks like the actual liquid containment part of this (you know, the inside of a can) is a little over half the size of the can so it looks like your tallboys will be really tall to get 16oz of chilled liquid refreshment.
Link via: Gizmodo
