You know they say you shouldn't be using it as a "doo[doo]" list.
OK, here is my "never again" experience with this.
About five years back, I went up for a flight with my mother to visit relatives in East Texas--about 1 hr away. We had lunch and I had a couple of Big Texas Cokes with lots of ice. I did visit the restroom, and was ready to go. On the way back, instead of going straight to McKinney, I thought it would be nice to get a landing in at Mesquite.
Well, I don't know, but after that, I got on my way for the 15 min flight up to McKinney, and I really had to go--BAD!
I landed, fast taxied to the chocks, pulled the mixture, took out the key, and shut off the master. I told my mom, "Wait here!" and ran for my life for the FBO. Super embarrassing as there were plane watchers and other pilots seeing me run for my life. They actually asked me if I was OK, and did I need help? I had to say, as I was running like I was on fire, "Just have to pee!"
. . . and you thought this would be about my mother, right?