Write a story about an event where reading forwards is in the perspective of one character, and reading the sentences/paragraphs backwards is in the perspective of another character.
Bonus challenge: make the characters opposite, e.g. someone being chased and the person chasing them.
Write a story that uses time in an unusual fashion, e.g. works backwards, skips around, accelerates/decelerates.
Bonus challenge: map your word count to measurements of time, e.g. 60 words, or 12 paragraphs, or 24 words on 7 lines.