How can you tell this plane has been to Oshkosh (or, to be fair, maybe Sun 'n Fun)? By looking in the passenger side pocket and pulling out this airsickness bag that has obviously been put to another (much cleaner) use - as a departure sign for leaving the big show. It always seems to turn out that way - you spend considerable time planning for the Fisk arrival, printing out all of the possible signs you might need for various scenarios. Then it comes time to leave at the end of your stay, and you discover that you didn't spend much time getting ready for the DEPARTURE! Or, possibly, your departure sign blew away in one of the storms that inevitable hits at one time in the week.
Yup - you need a quick "VFR" sign, and you've got nothing to make one with - no printer, no pad of paper, and not even an old kneeboard note - but you DO have a barf bag and a pen.... and since you haven't used, (or damaged) the bag in a way that prevents it from fulfilling its intended duty, it goes right back in the pocket for a future occasion. Hopefully, that's the next big show, and not, well... that other thing.