You might be familiar with the “whoosh” sound a turbo’s blowoff makes. The Subaru STI’s blowoff valve makes a decidedly more “organic” sound.
An enterprising Subaru owner decided to hook a duck call up to his turbo blowoff valve. Instead of the distinctive “whoosh” sound this car makes an extremely loud quacking sound. The bystanders can hardly contain themselves every time the driver lets off the throttle.
I think this is a mod most waterfowl hunters can get behind.