Brain-enhancing drugs work by focusing brain activity... for better or worse

It's late at night and although I want to finish this post, I'm pretty shattered. At the moment, I sorely need to boost my concentration and attentiveness and stave off the effects of fatigue. In lieu of actually getting some sleep, the ability to pop a little pill that will have the same effect sounds pretty enticing. Unfortunately (or perhaps luckily), the closest thing I have available is some coffee in the kitchen.