The Daily Beast: The Amazon's Secret Super-leaf

Discovered in the depths of the Ecuadorian Amazon, guayusa is a type of holly that, when brewed in boiling water, gives the jolt of a cup of coffee without the jitters, and has double the antioxidants of green tea. And it's about to make a splash--so to speak--in the global market.

http://www.thedailybeast.com/articles/2014/08/29/bye-bye-latte-hello-guayusa-why-the-amazon-holds-the-secret-to-a-cleaner-healthier-caffeine.html