Does anyone have any good tips for keeping energy up?

Ok, so it is Wednesday and I am running on empty. Over the weekend I came down with a touch of something and while I don’t feel bad enough to stay home and sleep I am still dragging. Yesterday I drank about 3 cups of tea to keep from dozing off, but it wasn’t enough. Today I am facing the same problem and have graduated to energy drinks (sugar free).

I want to know if anyone has tips (non-caffeine related preferably) that they use to keep focused at work when they are tired and feeling less than 100%?