Coffee doesn't seem to really help me aside from keeping me from falling asleep for a short time (~40-60 minutes maybe). I used it most heavily (2-4 small or medium cups a week) when I was suffering from undiagnosed sleep apnea, but even now I occasionally have some when I feel I must be extra sure not to get sleepy, and it doesn't really seem to help me focus and wears off quickly. Does coffee not work on certain people or is there some factor I'm not aware of?
Thus spake Eliezer:
It seems that many here might have outlandish ideas for ways of improving our lives. For instance, a recent post advocated installing really bright lights as a way to boost alertness and productivity. We should not adopt such hacks into our dogma until we're pretty sure they work; however, one way of knowing whether a crazy idea works is to try implementing it, and you may have more ideas than you're planning to implement.
So: please post all such lifehack ideas! Even if you haven't tried them, even if they seem unlikely to work. Post them separately, unless some other way would be more appropriate. If you've tried some idea and it hasn't worked, it would be useful to post that too.