BrainFlushI can't vouch for the *practicality* of this particular device, but the physics seems sound... they're stabbing your drink to the bottom with lots of non-melty ice pokers (more surface contact = more faster cooling) and that low liquid line when empty presumably shoots up to the top as the ice lid goes on. \o/ science!
(I did have to laugh at their beer suggestion though... who wants cold beer at the expense of flat beer?)
billnyeWhy would beer be flat? If you mean because of the 30 secs - 2 mins it's been out of the bottle, I'd be okay with that; it's nothing. Or for another reason?
mcmcHitting a beer with that much surface area will likely cause massive nucleation and release almost all the carbonation.
Said another way "you'd loose the bubbles dude!"