What are some similies starting with as funny as .?

Sure, here are some examples of similes starting with "as funny as":

1. "As funny as a clown with a banana peel on his shoe."
2. "As funny as a stand-up comedian performing for a crowd of laughing hyenas."
3. "As funny as a sitcom blooper reel on repeat."
4. "As funny as a joke that only a cat would find amusing."