TD - yes, that does look like a Baker;s cyst from the position. Funny - would not have thought that related to your previous issues, and like Neil, I didn't think they would spontaneously appear and disappear. Got yourself a sharp needle?
DV - you might have me talked into a diesel Mini for myself now! My diesel truck (F350) is horrible on gas consumption but of course, it's pretty huge. Thse numbers are impressive. As for nitrogen - new cars in the US come with that standard now - which is a pain as filling is an issue - so I just top up with air.
London to Brighton race? Now we're talking! I'll be driving my 1902 Delahaye - a lovely French lass with a body to die for. My consumption will likely be about 10 mpg - and it will take me a while to get to Brighton. I will start around 7.30 am from Hyde Park and expect (Ok, hope) to arrive on the pier around 2.30 pm (cutoff time is 4.30 pm). I think your idea of a race is fabulous - you're on! I don't think you'll need much, or any, start given my speed. Your kids are welcome to a ride - we'll be on Regent Street all day Saturday Nov 3rd. In fact, any and all from this wonderful thread are welcome to "party" at my car on Saturday.