Compressed air cannons are lots of fun for launching paper rockets. Turns out they are also pretty useful for indie films. What? Why would an indie film director want to launch a paper rocket? Actually, the compressed air can be used to throw a small pile of debris, creating a small "explosion" for an action sequence.
The awesome guys over at Realm Pictures came up with a great film that shows the entire setup for creating such an explosion, including the mentioned cannon.
They are also trying to fund their ambitions underwater indie film via kick starters, and share the plans for this cannon and a bunch of other cool film DIYs with backers (including the waterproof LED strip light we featured a while back), so give them a call on their Kickstarters page.