An easier way to maximize the caffeine intake would be just to use caffeinated water in your coffee pot.

Krank2O is made by the same company as Jolt Cola, and there are also other X-brands, like Water Joe, and the like.

Also, having done a small study on caffeine in high school, I've learned that it'd take about 700 cups of coffee in an hour to actually kill a person, which is physically impossible (at least, I think it is). I mean, even drinking 270 triple shots of espresso would be a bitch to get in you in the space of a few hours, but could possibly be done.

Now, if you made thickass espresso with caffeinated water, you could probably kill yourself if you could down 20 per hour for a consecutive few hours. Of course, I don't know how you'd get the cup to your mouth what with the shaking you'd be doing after the first hour, but it's possible, I guess.

Besides, wouldn't Dr. Pepper go and fuck up the coffee machine?