There is always coffee (or tea!) time and mail time, and... Isn't it wonderful when you can combine both? Like on this postcard sent by Laura (the UK).
But, of course, you can go farther and sent a real cup of coffee, as Heleen (the Netherlands) did. She included the bottom, so I can reassemble it. But if I did and drank my coffee, I would drink her words and the stamps as well (including the cow!).
This postcard made of coffee packaging was my reply to Heleen's cup.