Here's how to take everyday sprinkler parts and convert them into a portable, hand-held rocket launcher! It's cheap to make, easy to use, and will send a pap.
Vintage Buckner Rainmobile Jr No. 180 Traveling Lawn Sprinkler Parts or Repair | eBay
How to Make a Powerful Handheld Rocket Launcher from PVC and Sprinkler Parts « Hacks, Mods & Circuitry