(wall of text warning)
This is a ground story, and the statute of limitations has expired....
It was the early 90's and I went to visit my brother in the LA area in August (it's HOT at that time of year)
We go to lunch, and I got a 64oz diet coke, and since he was a roofer, this was all done outside.
"Hey Jeffy, it's 2:30, and we have to get to Compton and get the roofing supplies for tomorrow. Let's go."
We get in the car, and traffic grinds to a halt. Stop, Go, Stop, Go.
Well, all of that stopping and going sloshed around inside me, and I had to go.
"Hey Chris, we need to pull over, I have to pee!"
"No way, the store closes at 4, and if we don't get there, I'll lose $2000. Go in the cup."
There's a 40 oz paper cup in the cab.
"Can I use this?"
"Yeah, sure."
I fill it nearly to the top. OK, about 1/2 inch from the top and there was no lid to be found.
"What do I do now?" I asked, fearing the CHP wouldn't like it if I littered, and even less so if I dumped out a cup of pee on their beloved highway, especially if they were behind us. (The truck had a flatbed, so I couldn't see behind us).
"Throw it out the window!" he yelled
"No!"
I rolled down the window, and I held the cup there, figuring out my options. Traffic started moving, and we were introduced to the Bernoulli effect in practice.
Yes, the pee started being carried off of the top surface of the mass and the airflow blew it... right back in the cab, on my face...
...and his. We were going about 45mph at the time.
"Ahhhhhhhh!" we both screamed
"Drop it! Drop it!"
"I can't! We'll get in trouble and it'll get all over the truck!" (as the pee continued to spray us)
"DROP IT, DAMMIT!"
I flung the cup, and to this day, I can still see the look of terror on the driver of the Cadillac in the lane over as the paper cup exploded all over his radiator grill and splashed his car. I am so sorry if this was you, reading this.
My brother sped off.
I looked at him in terror, thinking that he was going to get unglued on me.
"Dude... that was wrong. So wrong. I get first shower when we get home."
25 years later, peeing in the wind, and being ****-faced still crack us both up.
(OK, back to aviation...)