Zinio is awesome and I have gotten many, many, many, many, many freebies off them.
My subscriptions include: Everyday Food, Food Network Magazine, OK! Magazine, Star Magazine (both free for filling out a survey), Nylon, Outdoor Photographer (got it free for whatever reason), Spin, Cosmopolitan (free for whatever reason
), and I usually get one offs and other subscriptions because they give me free credit from time to time, and when something is messed up, they usually give you a free copy of whatever you want.
Reader's Digest is in there too, and I'd highly recommend you use them for subscribing as they're universal. You can look through your stuff on Mac, PC, Android, and iOS.
On Newsstand I have Huffington, Cooking Light, Time (both free because I'm a print subscriber), The Magazine, Engadget Distro, and The Next Web Magazine.