I know this may sound boring, but water.
For similar reasons as Rep said really, I'm heavily into fitness, so water just goes hand in hand. I aim to drink anywhere from 2-4 litres throughout the day. It keeps me hydrated, refreshed and calm. I do like soft drinks as well, but to be honest I have gone off them a lot in the past year or so.
Alcohol wise I tend to stick to drinks I know and like. Beer being my go to drink really, my favs being San Miguel, Peroni, oh and Desperado too.