One of my local coffee houses offers a drink which I would like to think was inspired by the many conversations I've had with the barista, Larry Tritel. The drink, which they call Espresso Coke, is one or two shots of chilled espresso mixed with Coca Cola and poured over ice. Mine has Diet Coke, of course, but the result is a caffeine punch. I'm not a fan of Diet Coke but I don't think they carry Coke Zero.
Sounds a bit weird - still I might try this out at home.
@Charlotte74 Coke sold a similar product for a short time a few years ago. It was called Coke Blak. It did well overseas but not in the US. American's often lack a tolerance for new food items. http://goo.gl/tNdS