What are some creative apocalypse themes?

There needs to be a cause. The most common and explainable ones include:

- Science experiment gone wrong

- AI that becomes too advanced

- Crazed cyborgs

- Nuclear war/disaster

- War of some kind otherwise

- Terrorism

- Leader gets killed (leads to above usually)

- Dictator government comes to power

- Large volcano erupts and blocks out sun

- Asteroid

- Aliens

I'm writing a dystopian story for NaNoWriMo right now, (post apocalyptic) and am not saying what happened. History was forgotten and no-one knows, so the story is about people, not the setting.

(As the writer, I know what happened and give clues to the reader, but it will never be revealed)

Everyone loses their memories, to one degree or another. Businesses fail. Millions are in the hospital being spoon-fed by those who can remember just a little bit more. Scientists are working hard to fix the problem but they can't remember basic biology.

Death and destruction can come in a myriad of forms. Readers will expect the characters to keep them guessing. A shot-up planet is merely the backdrop. Pick a reason and stick with it.

the 'dream manifestor' becomes engaged from some unknown and sudden reason. everyone's dreams and deepest desires come true.

A single movie/fad /song becomes so popular it takes over all culture and turns everyone into dull slaves. Culture slows and eventually . . stops.

Cannibalism follows because we have become too stupid to operate can openers and we forget fruits and vegetables are food.

Radiation

Aliens blowing up the moon. The moon causes the tides, stopping that will screw up everything. PS The moon is un-defended.

Religion is a virus that eats brain cells.

Television news prompts mass suicide.

Every one starves to death in traffic jams.

Preppers kill all non-preppers for laughing.

Aliens.