For seven dollars, plus shipping and handling (although I’m sure Hot Topic or Spencers will have it sooner or later) you get two mana potions. Each one is 40mL of caffeine saturated goodness.
It apparently has a citrus flavor, which is kind of a down, and they are each effectively 2 Red Bulls in one bottle. Supposedly you get 5-8 hours of jitter free energy from drinking just one of these, but the jitter-free might be over exaggerated, but when you are moving the mouse around like a kid with ADD and striking the keyboard in a thunderous fury, I doubt you’ll be able to tell the difference til you hit the city and things slow down.
For now it’s only available in the US, which sucks for all the foreign players of the game. It’s not technically an official Blizzard product, but another one of those “by gamers for gamers” things, like I said, $7 for 2 of them, plus shipping.