Join Pepsi World to get a newsletter and be eligible for a bunch of sweepstakes and freebies, including the Aquafina sweeps listed on another thread. Also I was able to get a coupon for Buy one 20 oz. Aquafina Sparkling and get one free. As soon as I click on the link in the newsletter for a sweepstakes, I am automatically entered. (thread also on Sweepstakes)
Even though it said one coupon, I was able to print additional ones, and each coupon looks valid.