What's your preference?
Runners’ World has a great discussion going on in the forums right now: What’s better, Gatorade or Powerade?
As a dieter, you learn that all sugary drinks are bad. Lay off the soda! The juice! The sports drinks! For a long time, weeks into marathon training the first time around, I refused to bring anything with me other than water (or Nuun tablets). I mean, why would I want to take in any extra calories?
I remember a sweat-soaked 19-miler last summer where I had 40+ ounces of water over the course of the workout but still ended feeling dehydrated. Then I learned about the wonder of Gatorade from Nancy Clark. From last summer’s 20-miler:
I do think the Gatorade was a good idea. I figured that I had about 90 ounces of fluid between when I got up that morning and when I finished the run, and I did not pee until an hour after I was done. That is crazy! You try drinking 90 ounces of liquid on a normal day and not go to the bathroom constantly! The salt consumption really helped me retain the water, and I did not feel as light-headed or groggy at the end of the run.
Ever since then, I’ve been a fan. But too timid to try anything else out. When you have something that works, you tend to stick with it. But sometimes its Powerade that’s on sale.
The forum is pretty split on the Powerade/Gatorade divide. I have to say to all the people who are like, “no, you really should try x product that is only available mail-order or in specialty stores!” … yeah, that’s nice, but at the end of the day, my fuel choices are probably going to be what I remembered to pick up from the grocery store the night before. If I never try that stuff, I won’t know what I’m missing. 
And sure, Gatorade and Powerade are sugary … but that’s the point. You can’t perform an athletic event for 2+ hours without some sort of carbs.
So, peanut gallery: What do you guys prefer for liquid fuel or rehydration?