This summer, your Commando dreams are reality, thanks to Japan's Marudai Corp. For a cool ¥28,350 ($363), the company will sell you its PET Bottle Launcher RPG-7 kit. It contains all the parts to make your own bottle launcher.
Once you have the RPG-7 built, you fill a plastic bottle with water, set the launcher, pump air into the launcher (with a bicycle pump), and pull the trigger. Then, whoosh! The plastic bottle flies through the air, leaving a trail of water. The launcher even has a realistic recoil.
The PET Bottle Launcher RPG-7 is aimed at adults and is 18 and up. When I say "aimed at adults", I do not mean "aimed at adults."
R・P・G！ あのロケットランチャーを再現したペットボトルランチャー「RPG-7」が発売中 [Kotaku Japan]