Once upon a time, I was riding in the back seat of a beat up old Cessna 172 while two buddies up front were flying. This plane didn't have any headset jacks in back, so I couldn't hear what they were saying. I was just checking out the scenery and enjoying the ride. We were taking an easy trip over to another airport restaurant and back.
One guy up front turned around and said something to me, then faced forward again. I was just reaching up to tap him on the shoulder and say "what?" when buddy #2 suddenly took us into zero-G. Of course I wasn't belted in, so I levitated about a foot off the seat. He wasn't too smooth with the maneuver, so we actually got some negative G's and fishtailed around some, kicking up a handful of dirt. I started to cuss him out when the chocks that had been sitting in the baggage area floated forward and knocked me in back of the head. Then he
finally got worried about the engine coughing from fuel starvation, so he leveled out and I landed sideways in the seat with the chocks' rope tangled around my arm.
Lessons learned all over the place. That could have gone wrong in so many ways...
Airplanes are fun.