I have two favorites. The first is the rear view mirror. I was driving on CR 228, a quiet snow covered dirt road with no traffic. I tell you that so you won't think I was endangering other drivers. I noticed there were several options of buttons on the lower edge of the mirror, but all were too small to actually discern what they were for. I hit one and ON-STAR came on! I started pushing anything to try and turn it off until the nasal female voice came on saying "On-star, please state the nature of your emergency." With my only emergency being how to turn to off On-star, I told her I was in a rental car and had accidentally hit the button and couldn't figure out how to delete the request. "I will end this call if that is appropriate." (nasal voice) "YES thank you!" (me)
The second fun adventure was trying to figure out how to put gas in the car. I was driving up to the pump and hadn't checked to see which side the gas cap was on. I picked wrong and had to back up. Then in what I thought was a thorough search, I couldn't find the cap open button anywhere. I asked the guy next to me if he had any suggestions. We looked in all the 'usual' places, checking seat, dash and under dash. Nope. So I checked in with a woman who had just driven up to the pump in front of me. She was quite hesitant to open her window. Do I look scary? I explained my odd request and she suggested the 'usual' places. Telling her they didn't pan out, she said "How about just pressing on the gas cap and seeing if it opens?" Voila! Cars are so modern, this one is way ahead of my experiential background.
My office partners and I think there should be an app for rental cars...