The best fuel for me is having a healthy physical life away from the computer. I've noticed that being in good shape helps a lot when pulling long shifts on the computer.
As far as beverages go, I usually drink more tea than water (mate or cold-brewed ginger and green tea). For a hard boost, espresso is the way to go but it doesn't last long and puts my metabolism into hyperdrive.
As far as beverages go, I usually drink more tea than water (mate or cold-brewed ginger and green tea). For a hard boost, espresso is the way to go but it doesn't last long and puts my metabolism into hyperdrive.