Dana Dolfi's people-stopping calliope is made from ship and train air horns. It won't be hard to find The Great American Horn Machine at Maker Faire Detroit. It's really loud. The horn machine can play a range of 24 notes through a MIDI controller. Dana is a pipe fitter/plumber by trade and a collector and builder for fun.
Learn about more makers who will be at Maker Faire Detroit here.
Mark Frauenfelder is the founder of Boing Boing and the editor-in-chief of MAKE and Cool Tools. Twitter: @frauenfelder. Come and hear Mark speak at the ALA conference in Chicago on July 1.