Dear Tom.
During my time I have given various car lifts to actors and writers etc. at conventions. These are very interesting and sometimes odd experiences, especially when an unsure actor starts to mould their personality to fit the demeanour of their co-riders. Or they, or I even, are a fountain of knowledge and witticism to the others for the duration. (I have had liftees E-mail me afterwards about books I have quoted details from).
You must have had lifts from a fan, or indeed given a fan a lift. Are there any times when this has happened and something notable happened, or a fan has divulged something really insightful? (I know you have always spoken insightful stuff to us).
Some quick related stories:
On one of my lifts, I had previously fixed some broken-off, little, blind-spot mirrors back onto the car's wing mirrors with gaffer tape and put the tape in the glove box. Before giving people a ride I realised that if the glove box accidentally opened in transit, it might look like I had the gaffer tape to try and abduct the actors. This is a common running joke amongst the fans and the people behind the show, however for just in case it caused an difficult moment, I decided to dispose of it.
I've also realise that my car is actually an old blue box. It even has a gear box problem that stops me from using 'sporty mode' - which I've never used and is therefore a problem that I don't need to fix and don't bother too - like a Chameleon circuit. Also like the Doctor I end up explaining things to my driving companions, who have sometimes been the actual DW companions.
This is an amusing analogy that had occured to me recently, but having an adventure whilst helping people and flexing the intellect isn't really a bad thing with done with a sense of mirth in my opinion.
Skeptic.