CAFFEINE

The Encyclopedia Galactica defines caffeine as an extremely complex carbohydrate found in certain beverages, and notes its energizing effects on certain carbon based lifeforms.

The Hitchhiker's Guide to the Galaxy states that the most highly caffeinated beverage in the Universe was an Earth drink, now sadly on the verge of extinction, called Surge, the effects of which were said to be like sticking a penny in an electrical outlet while standing in a tub of water. The drink's creator had this to say: "Never drink more than one can of Surge unless you are an Indian elephant with severe physical depression." Though this man's name is unknown, it is known that he worked for the Earth-based Coca-Cola Company, of whose wisdom we will learn later on.