The July issue of Empire magazine has a battle of good vs. evil between the heroic Batman and the villainous Joker. The dual covers were created to further build anticipation for The Dark Knight's July 18 release. The magazine asks you to "choose your allegiance" when you choose one of the two collector covers, knowing that true fans will scoop both.
Actually, there is also a third limited edition cover of a "jokerfied batman" that features a Joker-style, carved HaHa and a big smile on the dark knight's face. This joker-themed covered is hands down my favorite out of the bunch.
The multi-cover trend has been on the rise with several magazines hoping to capitalize on fans' desires to own each shot of their favorite star or movie covers. I must say that if they start over-doing it, the practice will lose its magic and uniqueness. Multi-covers should be reserved for truly special occasions such as this example of Batman vs Joker, or the recent 50th anniversary of reFRESH magazine.
Check out three recent magazines with multiple covers: