Dare: Have a character physically restrained in a humorous manner. (Ex, Charrie is pushed into a pit of rotting mackrel) Bonus: Have the escape be even funnier. (Ex, charrie flops out of the pit just like a mackrel, while making a witty one-liner.) .
Dare: Have a rodent cyborg from the future called "The Verminator" appear. Bonus: Have them say "I'll be back" or any similar-sounding phrase that makes sense in context. Double Bonus: If you write them with a phonetic Austrian accent.
Dare: Write a post where your character flat-out disagrees with everything that anybody says.
Dare: Have your character quote 3 famous song lyrics in a single post. Bonus: If the songs are from the same decade. Double Bonus: If all of the lyrics make perfect sense in context.
The bottom can also apply to movie lines or other famous quotes. ^^