My neighbor was cleaning out his kid's old stuff and gifted me two gumball machines. I replaced the cracked glass top with a laser cut acrylic cube and mechanized the dispenser. There is a Python program running on the Raspberry Pi that allows you choose a trivia category (originally Science, Adult Themed, Burning Man History, or Random). If you get 3 questions right out of 5 tries then it dispenses a gumball. I've since modified the program so the categories are general science, math, physics, and local history. It now lives in my classroom. The program contains a list of my current students and it only allow them one attempt every 24 hours.