Milk is my fave. Always has been. I've almost never had milk expire at any house I've been at.
That said, I'm actually really surprised by this poll. I've never liked soda much - I especially hate Coca-Cola and Pepsi - and I feel like I never drink it, and nobody on my dad's side of the family (the side I grew up with) really drinks coffee, tea, or alcohol. In fact, I don't think we even have a hit drink machine - which is just as well because I hate coffee and most alcohol anyway.
Hmm, I drink coffee every morning and practically can't function without it, so that's probably the one. But I also drink a lot of sparkling mineral water, and some alcoholic drinks are pretty good so taste wise I'd probably go with some cocktail. Tea is occasionally very good for relaxation or warmth. I can't decide