There is something I use called "Energy Up Time". I have Multiple Sclerosis and a real problem with my energy levels. I am also a long distance runner. My natural medicine doctor recommended it. It's all natural (I know I know, just cuz it's natural doesn't mean it's good) but in this case it's ok (for me). She wanted me off caffeine (I drink a lot of coffee) and gave me this as an alternative (it doesn't rev my immune system like coffee does). This helps me get out there on the train even when I am drained at the end of the day.
The ingredients from the label: Spirulina Blue Gree Algea, Wheat Grass, Alfalfa Leaf, Caffeine, Papaya (fruit), Silica, Cayenne (fruit), Siberian Ginseng extract, Echinacea (herb), Ginko Biloba extract, Carnitine (tartrate), CoenzimeQ10, and Chromium.
I can buy this at our local grocery store, at the Sun Harvest and even at 7-11 in the little packages usually reserved for truck drivers.