Clever, outside-the-box-style pranksters... you're welcome. The DIY Fortune Cookie Kit ($10) is a great novelty for parties and a great resource for mayhem. It includes twelve pre-baked cookies, instructions on how to make and insert your own fortunes, and - the kicker - resealable pouches to make them look authentic! Think of it as payback for every inaccurate or unlucky fortune that's ever ruined your meal.
(Note: Cookies in picture are in original wrapping, not resealed wrapper.)