[Darksheare]

I learned to snorkel in a vo-tech pool that had a 13 foot 4 inch deep end for the high-dives.
(It was a T shaped pool as well.)

I practiced 'hovering' in the deep end.
Basically I deep breath a few times and then dive.
Well, I was upside down, hovering in the deep end when the largest guy of the group decided to high dive, above me.
I was looking upwards between my feet, since I was upside down, and wondering who would be stupid enough to be on the high dive when no-one was supposed ot be there.
*Ba-SPLASH*
He bellyflopped from the high dive.
I did not know that one could feel a pressure change from someone landing in the water above you.
Cripes that hurt.
Haven't done anything similar since, and haven't found anyplace to do such anyway.

[Fedora]

I did not know that one could feel a pressure change from someone landing in the water above you.

Ouch! Did he land on you or was it the pressure alone that you felt?