"Have always been interested in the mouse population on the Underground: I believe that studies have shown that each deep-level tube line has a genetically distinct population, resulting from them being isolated from each other.
My own mouse incident happened at Westminster's fine new Jubilee-District interchange. I was on my way to a seminar for senior managers in my organisation, and had to change from the District to the Jubilee lines in the morning rush hour. It was very busy, but on one of the levels of the new station, there was a petrified mouse stuck in the middle of the floor, trying to reach the edge, but failing due to the large number of people walking past. I felt sorry for the poor thing, and bent down, saying, 'hello - are you lost then?'. A moment later a voice behind me said, 'Good Morning, David!', and to my horror found that one of my senior colleagues had been standing behind me, as I was speaking to the mouse... I muttered an embarrased, 'Good morning' back, and joined him for the rest of the journey.