When you're a farmer, but your real love is demonstrating the laws of physics.
Also, are those guys stomping on the trampoline to heighten the other guy's bounce? I didn't know you could do that. Perhaps because that's the sort of information that people hide from their children.
Tractor-mounted irrigation pump - GIF
Tractor plays percussion in bluegrass band - video
Tractor-powered wood chopper - GIF
John Deere tactical tractor