The "energy drink" I am reviewing today is good ole convienince store coffee.
Drip-brewed coffee has about 145 miligrams of caffiene per 8 oz serving.
That's twice as much as most of these e-drinks and 3-4 times as much as soda.
It's so cheap, an empty cup almost costs more.
The caffiene assimilates fast, especially if you add about half a teaspoon of sugar for every 8 ozs.
It's lo-cal and widely available. You can make it in your home even cheaper.
For these reasons, I feel coffee is the 'open source' energy drink.
Quit spending all that money on redbull - redbull exists primarially as a mixer for vodka.
EDITED TO ADD MORE NUTRITIONAL JAVA INFO:
Type of Grule:mg of Caffeine
Brewed (8oz): 60-135 mg
Drip (8oz): 115-175 mg
Instant (8oz): 65-100 mg
De-Caff (8oz): 1-5 mg
Espresso (2oz): 100 mg
Tea (Regular, 8oz): 40-60 mg
Tea (Green, 8oz): 20 mg