My 12 year old nephew gave me a one word prompt that broke my writer's block
I was stuck on the same opening line for 3 weeks when he walked by and said "write about a bad sandwich," and I cranked out 900 words in one sitting, so now I'm wondering what weird constraints actually get other people unstuck.
My buddy Dan got past a 6 month dry spell by making himself write the whole thing as a text to his mom. Something about the format just unlocked it, he said it was the bad grammar and not caring if it made sense.