Personally I've become a big fan of tea. Hot and iced. In my opinion most teas don't require any sugar or require very little to offset a bit of bitterness. 9 times out of 10 I use no sugar at all. And that 1 time I do it's maybe half a teaspoon because the tea in question has a bit of bitterness or because I let it sit for too long.
Tea also has the added benefit that if you make it per glass it forces you to get away from the computer for a few minutes. Plus the aromas and flavors are, in my opinion, more numerous and pleasant than all the sugary drinks out there combined. Tends to be noticeably cheaper too :)
Seconded. If you live in a metropolitan area, you will likely have a Teavana or other chain/mom & pop tea store where you can go in and smell or try all of their varieties.
You'll easily find half a dozen different teas you like ranging from the classic black teas to exotic varieties that taste like supermarket sugar drinks (like strawberry lemonade - one of my favorites at teavana). The latter usually require less a 5g bump of sugar to bring them to the level of retail drinks.
Tea also has the added benefit that if you make it per glass it forces you to get away from the computer for a few minutes. Plus the aromas and flavors are, in my opinion, more numerous and pleasant than all the sugary drinks out there combined. Tends to be noticeably cheaper too :)