The thing that worked best for me was a bottle of room temperature water with just a touch of salt thrown in. Gatorade and such things as that often upset my stomach when I drink them due to thirst. It's not to say they don't work, as we know there is science to back it up, my guts just don't dig it. I also cannot drink (chocolate) milk for recovery right after a ride or I puke...
When I was riding enough for things like this to matter I would carry 2 bottles lightly salted water and typically a gel just in case I bonked out somewhere. Later on I just got where I would stop for a snickers if I felt the need.