My dad — my parents live in Manchester, Tennessee — is retired from John Deere, but that’s only given him more time with tractors, not less. He and my mom are serious antiques collectors, and while she heads for the linens and Depression glass, he can spot a rare tractor part or tool from a mile away. Also: Actual tractors. At least the wrenches and oil cans and other portable items he collects are easier to store and organize.  He does a great job of documentation and has an impressive library of tractor advertisements, manuals, giveaways and other tractor-related paper goods. He even led a workshop on “Industrial John Deere: In the Beginning” at the recent Gathering of the Green conference in Davenport, Iowa. My dad also likes fish. Not to catch or to eat, but to stock the pond at his tree farm/nursery. The fish eat the algae and pretty much keep the ecological system going strong, although I think my dad likes to talk to them them while he’s mowing. Just as long as they don’t talk back …