So this is a weird story.  I got a coffee out of the fridge, and set it on the table.  I didn't open it for quite a while, because I was finishing some emails..  So when I finally got to it, it had condensation all over it.  I thought, "Oh darn, I let it warm up."  But I opened it anyway, and the tab broke off. The entire thing was frozen hard as a rock.  Very strange.