Reacting to ex-tennis player Roger Federer's post where he was seen riding an electric scooter around the Stanford University campus, ex-Olympic skier Lindsey Vonn said, "Hahaha, you're hilarious." "Back at it fast and furious. Bay Area edition," Federer had captioned the post. Federer, who retired in 2022, won 20 Grand Slams in his career.