As cold as you can get it before turning to ice.

While we're talking about beer temp here's a cool trick for you guys to try.

Put a beer in the freezer and just before it freezes take it out. Make sure the beer in still 100% liquid then try hitting it on a table or try to take a month full that seems to work the best and the beer will then freeze instantly. It's pretty cool to see and also I think this works better in long neck bottles so maybe try with a corona