Another drink is accelerade, but its not as much of an energy drink as it is a drink to help your recovery after the ride, and it helps you start to hydrate your body before a long ride
Accelerade is one of the new energy drinks. Someone decided that for long efforts, you need protein so Accelerade has some disolvable protein in it. It's supposed to taste awful. Hammer makes their own version.
You can try Hammer HEED (High Energy Electrolyte Drink), which I just started using. After drinking Gatorade for 3 hours, I feel like puking because it's so sweet. HEED doesn't taste sweet, and it seems to work pretty well for me.
Remember none of this stuff has any scientific proof behind it. Hammer's marketing is pretty effective though, so maybe check out their website.
You might do just as well by eating a banana and a bagel at the halfway point, and sticking to water.