You can also drink other things than just plain water, and keep hydrated as well!
Drinking most herbal teas (non-caffeinated) - or green tea, etc is probably just as beneficial (if not more so) than plain water, and will also keep you from getting dehydrated.
I also tend to add lemon (or lime, which I prefer!) juice and/or slices to my water when I drink it (at least when I'm at home) - yummy
I also enjoy a product that I buy fairly regularly - it's green tea with ginseng & honey - it's great to drink either cold from the fridge, or just room temperature, when the flavor from the honey really starts to come out...