Personally, one of my favorite beverages. Additionally, there is a lot of hype about coconut water these days. Whats so special about it? Well it naturally contains electrolytes that are commonly found in sports drinks and provides a low caloric value per serving comparatively.
Re-hydration. A study, cited at the bottom, examined the restorative qualities of coconut water, a typical market sports drink and plain water after exercise induced dehydration. Their data indicates that coconut water exudes the same plasma level (blood level) measurements as consuming the sports drink and similar blood glucose response post ingestion. It was also easier to ingest and caused less nausea and had more "drink-ablility" (as Budweiser would say). When choosing foods and substances to place in our body, going natural is always better. You avoid mysterious unwanted chemicals and simple processed sugars.
Give coconut water a try for post workout re-hydration. I like to make a protein shake with it by taking 8oz of coconut water, 1 scoop of vanilla protein powder (70 cal, 13 g protein) and stevia to sweeten. This proves to be much healthier in maintaining your insulin response, is natural and satisfying.