Some years ago, I took a friend and his teenage son for a ride in our Cessna to survey some tornado damage to one of their neighbors' farms near Hays, KS. The air was a little choppy, but they did OK until final approach for landing when, for no apparent reason, the kid blew lunch all over the instrument panel (I mean "lunch" literally, as we had just finished a meal at church, and some of his projectiles were recognized as pieces of the potluck!). I worked all afternoon to clean up the plane as much as possible before the stuff dried, but never really got everything right until the next annual inspection when, as required by the inspection protocols, I removed the entire interior of the plane. Yukkk!
I wish I had some of the products mentioned in this thread at the time!