A really nice comprehensive guide on all kinds of caffeinated beverages is at Tech Manifesto:
There are many high caffeinated energy drinks on the market. Which ones work the best? In this article, Tech Manifesto will show you all the caffeine levels and ingredients in these products resulting in all night gaming experience.
Odd note: they put penguin mints in the list…dunno why.
Just makes you ask yourself why you’re paying $2 for a little can of Red Bull($5-$10 at clubs) that don’t even do as well as regular coffee.