London really is an amazing place to spot cars.
The cool thing is a friend of mine, was in London begin this week and last weekend, and he spotted quite a few of the same cars as youd did (for instance the Enzo). This means quite a lot of those cars are there on a daily basis. Must be just great to see them one after another.
Seems like your CGT, SLR, Enzo experience of a few minutes ago says it all