I just love the scienceblogs. Here's a totally brilliant piece celebrating - umm, reviewing - the advantages (and mentioning the negligible disadvantages) of going heavy on coffee (as I do). You'll think faster, memorize better, avoid all sorts of illnesses and battle stained teeth. Go for it! Well worth a read!
I even discovered that there's (at long long long last) caffeine infused soap to ease the waking-up process in the morning (ie have a nice shower and apply the soap liberally to your skin).