Talking of tennis and the problems that it brings along
This issue really intrigues me :)
-- where does a player or rather where does the ball kid keep the towel handed to him during match play--
For instance currently at the French Open the towel is placed on the line's person's chair --poor linesman-- but I know that is not a permanent solution; elsewhere is placed on the "serve speed display box". Infact in many courts especially on outside courts the ball kids are asked to place the towel on the court itself
We have comeup with technology to make line calls,
solution to correctly indicate when the ball hits the net chord,
come up with technology to measure not just the serve speed but also the speed of every shot that is hit,
but it surprising no one has come up with a solution to the towel problem!