UK resident? Use UKSEP15OFF to get the same discount. Gamefly's Coupon of the Month for September 2014 is currently at a decent 15% off. It works on most digital titles, except certain major releases where prices may be more restricted.
Each week, GameFly has various types of sales with different themes from their PC download catalog and the Gamefly Coupon of the Month can often be stacked with other coupons or be applicable for the sale's bigger-than-usual instant savings.
P.S. You'll need to login and head to the checkout page to use and see the discount from the coupon. Look for the section "Apply Gamefly Coupon" just below the billing address. If you were wondering where you enter the code for some Gamefly discounts, now you know.
Looking to give Gamefly a try? The best way to do this is to use their 10-day free trial coupon code TENDAY above. Subscription is a lot cheaper now at only $5.95 per month (they use to be $13.95+!).
The worst thing about being a console gamer is spending what little money you have and you end up buying a completely terrible game - this is even after reading all the reviews available out there! Gamefly's monthly service where you can rent unlimited amount of games is your best defense against bad games (or simply games you don't find as enjoyable as everyone else does).
Sign-up is straight forward and delivery of the games are of course free shipping both ways. There are over 8,000 titles to choose from in Gamefly's library of games. The free trial ends on the 10th day so if you don't find the service useful, you can easily cancel within your account profile.