Roy Lowry and his team have launched 55,000 bottle rockets, each reaching an altitude of at least 100 feet, all in 5 minutes. They're still awaiting world record verification by Guiness. Sounds like fun. Actually, it sounds like something Nemo would try! (see Nemo's timelapse shot, below)
PS: I didn't ask permission to link to any of these images, so if you want me to take them down, just let me know!