NUUN is a no sugars, no carbs, non-fizzy hydration tablet. Just break one tablet in half and drop both pieces into a bottle of water. I started using NUUNS back in fire academy and they work great! It looks like a fizzy alka seltzer when you first drop it in, but it's completely flat-tasting once the tablet is disolved. It comes in a 4 inch long waterproof plastic tube (12 tablets) and in several different flavors. They are sold at most running/outdoors-type stores. I always keep a tube of them in a small gear bag on the truck. At about $6.50 a tube, there are a little pricey. But I feel they are worth it, especially as a nice change of pace with daily hydration, during rehab on a fire scene, and while working out.

http://www.nuun.com/nuunis/whatisnuun.html