I've always kept a bottle of vitamin B12 around the house for Hangovers, For the Use Of; learned about their usefulness in that regard way back in uni. Last week, I wasn't hung over but was a little foggy/drowsy and needed some mental acuity, so I popped one, and within a half hour I felt a rush of energy, and enhanced cognition. I may have been operating on a vitamin deficiency (doubtless, as I'm a bachelor working an off shift and habitually eat junk food), but every day since I've been popping a B12 on wake-up, feel the impact within half an hour, and now after continued daily usage I feel like freaking Superman all day, no more drowsiness on shift. Anyone else find vitamins or supplements that enhance their daily performance? Only downside I've found to B12 is that it *is* an appetite enhancer. It's water-soluble so you can't give yourself a lethal dose, though I'm not megadosing with it anyway.