I don't drink coffee

At work, we have several places to get coffee without leaving the building depending on how much of a connoisseur you are. There is the lowest level, the free stuff available in every break room on every floor. The middle level is available only in the mornings in the cafeteria. And the highest level is available in the convenience store is Starbucks. All that said, I often hear "Let's get coffee" when someone wants to talk in the morning. Furthermore, its the same people offering to get coffee with me again and again. It also nearly never fails that they ask, "Aren't you getting coffee?" when I do not myself pick up a cup wherever we end up. I've decided I need a t-shirt or sign in my cube that points out that I don't drink coffee as a reminder to these people. :-)