The Machina Magnifica was the fabled "lost invention" of Leonardo da Vinci. Leonardo accidentally left the plans for his greatest invention back on Earth.
In 3010, Fry and Professor Farnsworth found the lost plans in Italy, and, following a series of clues left by Leonardo to aid the shadow society of intellectuals that would follow, traveled to Leonardo's homeworld, Vinci.
There they reunited Leonardo with his lost invention, and with Fry's help built the machine. It was then revealed that the machine's purpose was to take revenge on everyone that had made fun of Leonardo, and made ice cream as a by-product. Fry, who had been told it's primary purpose was the ice cream, decided to put a stop to it, and while attempting to pound a nail into the gears with another nail, fell into the device, bringing it to a halt. As Leonardo tried to get some further use out of the Machina Magnifica, a gear fell on the great inventor, killing him.