Farm Hack: worldwide community of farmers that build and modify our own tools
I visited Four Seasons farm last year in Maine. They do a lot of open experimenting and share their ideas. Four I was shown were:  - washing machine converted to a large salad spinner
  - a hand drill with a mop on the end, plus a slicing blade and catching bag (for picking lettuce)
  - a 12-tine rake to which you'd attach a combination of hose segments specific to the seed row spacing you needed
  - a green house on rollers so you could start seeds undercover and then move the framework without replanting anything