We have coffee (and cocoa) available in the Library for 50 cents a cup. It's on the Main Floor, next the the check-out desk. Payment is on the honor system, and payments also cover the costs of additional coffee, cocoa, AND supplies (like cups).
If there is no honor, however, the system falls apart. Please pay for your drinks, and don't take the supplies.
And just in case you didn't know, we also have vending machines (snacks and cold drinks) on the Ground Floor.