San Francisco, USA
Run by local Chef Jean-Marc Gorce, this teeny-tiny place is more of an award-winning truffle vendor than coffee shop. However, the coffee is fresh and even if you just order a small house-blend for just $1 you'll get a free truffle (worth 75 cents).
Listen to the audio guide for XOX Truffles Free on WIP — starts by itself when you arrive, even with the screen off