I think this is a great site and have had it on my favourites for ages. It's about London Underground stations that are no longer in use. It's quite a big site and could take you several look-ins to read it all, but I am amazed at what is down there that you don't know about.
I use this quite alot and it has been brilliant, I have found my 4 grandparents as young teenagers with all their brothers and sisters still alive, as it was 3 years before The Great War, and the last time every one of their families was still complete. I think all 4 of them lost a sibling in action. http://www.1911census.co.uk/