This is how I feel right now - very much. I won't be able to communicate coherently until I make a DD's run.
On a related note, I was watching Will & Grace last night and Jack was trying to quit caffeine. At one point, he ran out of the room, screeching "I've got a monkey on my back and his name is Juan Valdez!"
(Comic appears courtesy of Toothpaste for Dinner, naturally.)