Upon recently having the car tuned up, I discovered I had quite a nasty oil leak. Therefore, attempting to keep the oil level at an appropriate level whilst driving it to the garage....I checked the oil to find it a bit low. I placed the dipstick on the back bumper and proceeded to add a quart.
Apparently, I then thought it would be a great idea to put the oil filler cap back on, close the boot lid, and drive to the shop....
...with the dipstick still sitting on the back bumper. DOH!