Barry Gibb service motion
Check out Youtube and the video "Barry Gibb playing tennis love and hope".
It's a charity event featuring Chris Evert, Martina Navratilova, the Bee Gees frontman Gibb and some other celebrity. Barry Gibbs serve looks awful. His groundies aren't that hot either, but how do you come up with a serve like that? Although his look with the headband has a great 70's/80's feel about it. Almost like some vintage swedish player.