Need an inexpensive way to launch promotional t-shirts into a crowd. Checkout this post at thebigmanual.com. It features complete plans and instructions for building a pneumatic cannon that will launch a rolled up t-shirt 100 or more feet into the air. The plans are free and the parts and materials needed to build this jewel can be found at your local home center for under a hundred dollars. If you’ve been wanting one of these cannons and couldn’t afford it, this might be the answer to your problem.