UPDATE (2:20pm ET): No need to enter coupon codes! There is a general Memorial Day Magazine Sale at DiscountMags that includes Popular Photography at the same price ($5 per year, up to 3 years) without the need to enter the coupon.
Other magazines that go for $5 per year as part of this promotion include Wired, Popular Science, ESPN (sports photography), and Glamour (fashion photography).
These are not auto-renewing subscriptions. Good for new subscribers or renewals. These are printed magazines delivered to your door!
The offer here is for printed magazines. Availability of digital subscriptions in conjunction with a printed subscription varies by magazine.
This offer expires by the end of day on Monday 5/27/13.
For some other magazines that are not part of this $5 sale, you can use coupon DAD20 for 20% off. The 20% off coupon does not work with the $5 magazine offer.
Original post after the jump for reference...