Decaf, not only for sick people.
On our take away cups in Amsterdam we even use it as a joke. And most of our professional clients don't want to buy it. But the non-believers are all wrong; there's really something happening in the 'decaf world'.
Don't believe the hype?
Maybe read this Sprudge article by the incredible Katrina Hof. (oh yes, yours truly is one of the interviewees)