So we've got the Zombie Apocalypse.
Upcoming is Wrath of the Gods, which will in all likelihood include things like end of the world scenarios like Ragnarok, or the Mayan Calender ending, maybe even Revelations of some sort.
Alien Invasion will include stuff like War of the Worlds, Invasion of the Bodysnatchers, Independence Day, and so on. Way too much to mine there.
Rise of the Machines will be stuff like Terminator, possibly Transformers, or Maximum Overdrive.
How about Planet of the Apes? Maybe a book on just straight up alternate endings and their post apocalyptic worlds? Or weather apocalypses like in Waterworld or Snowpiercer?