A car in solar orbit

The first Falcon Heavy carried a cherry-red sports car with a dummy in a spacesuit, because the customer for a test flight is nobody.

Test flights normally lift concrete or steel. This one put a Tesla into an orbit that crosses Mars's, with a camera on it, and the two side boosters came back and landed side by side on the same pad seconds apart. The car passed reasonably close to Mars in 2020 and is still going round.