The Fast and the Furious (and other Fs) retrospective activity

Recently I lacked some inspiration for a good technique suitable for the upcoming retrospective. As the team was growing in their agile way of working, I decided to leave it to the team to come up with a nice activity. I was very surprised with the outcome. A brand new activity which we called the Fast and the Furious (and other Fs).
This activity’s goal is to gather information about the sprint.