In the 1980s on locomotive-hauled trains I decided to note down the number of each coach I travelled in. After a while I realised that if I got up and moved into the next coach I could double the number of coaches I scored. Then I would move into the next coach. It wasn't long before I was moving along the train in order to sit in every coach for a short period.
I was sitting in a seat for a couple of minutes, getting up and moving to the next vehicle, then getting up and moving to the next ticking each coach off as I went and getting funny looks along the way.
I was then contemplating noting down the seat number I sat in in every coach which would have eventually lead me to moving from one seat to the next as I travelled along. I soon realised this was starting to get out of hand and I was becoming obsessed with it so I decided to discontinue this quest. I'm pleased I did, I still have my sanity - just.