Not my own idea, but one of the writing prompts from the "other site" that I immensely enjoyed. ;)

Earth sends its most distinguished diplomat to make a good impression. Then the alien representative introduces himself - Biggus Dickus.

Dead people came back alive and were sitting in rows. The rows were younger variant of Jesus Christ, Joseph Stalin, Adolf Hitler, and many, many more.

The school is filled with students, the most important figures from history from two thousand years ago up until recently were all here.

You came into that class you were assigned into with a teacher, she told you to introduce yourself to the class...

A man is running down a green hill, he trips and falls, and when he looks up he see the visage of death as his cabin is burning with the work of a lifetime inside.

( I thought of this a while ago in a brainstorm feel free to simply continue the story.) "The detective was sprinting down the alley-way, thoughts rushing through his mind, he couldn't lose this one. He turned the corner only to see his goal climbing an access ladder. He only just caught the man pulling him down and to the ground with a Thud!

The detective looked around noticing the rainbow colored cat at the mouth of the alley-way, the cat stared at him, and him at the cat. The floor opened and with no time to react the detective and the man fell into the rainbow vortex."

Humanity has discovered FTL travel. All trips in the direction of the galactic core vanish without a trace. Plotting the disappearances reveals two things:

1. They outline a sphere.
2. The sphere is expanding at the speed of light.

Bonus points if you don't do something like "the main character considered themselves the hero and the story is narrated from their perspective"