Well, Whadya Know

Why do tennis balls feel fuzzy?

Tennis balls aren't completely bald for two reasons. The fuzz
is there, for one thing, to slow it down. You might find that
hard to believe had you ever had to receive a cannonball
serve from John McEnroe, but there you are. It facilitates
rallies by increasing wind resistance and preventing the ball
from leaving the stadium on one bounce.

The fuzz also increases racket control by holding the ball
against the strings for just a fraction of a second longer
than would happen with a smooth ball.

[source: Just Curious Jeeves by Jack Mingo and Erin Barrett]

If all the blood vessels in your body were laid end to end
they would span the globe. But were this done, I doubt that
you would be in the mood to appreciate it.

If surgeons removed one of your kidneys, a lung, your spleen,
much of your liver, and more than half your intestines, you
could still live. But it wouldn't make you the best doubles
partner for tennis.

[source: 2201 Fascinating Facts by David Louis]