I noticed an article in the current Seattle Magazine that mentioned ageing eggnog. I'd never heard of this before, being a somewhat recent transplant to the Northern reaches of the world. For some reason, in South Africa, we never really got into eggnog, what with the 36+ degree C summer weather over Christmas!
The basic idea presented in the article was to put the eggnog (with alcohol) in a cool location - the author used her unheated garage. Now, my garage seems to stay around 45 degrees F in winter (at the coolest), so this seems like a dangerous thing to do. Surely the eggs will grow some funky bacteria?
Not so, according to this article on Chow.com: Old but not lethal
They do recommend using the fridge, not the garage, though!