I was trying to find an address online yesterday. I was aiming for 192.com or the likes but somehow stumbled upon Zoopla instead by mistake. It is quite interesting because they have a database (which is freely viewable) of house prices. I don't mean it is interesting because you can spy on how much your neighbour sold his house for (which of course you can!) but it is a good way of seeing how house prices around you are falling in the recession.
Take it with a small pinch of salt occasionally however - I did notice one flaw... When André and I got divorced I sold him my half of our house so the last selling price for his house is in at half of that of all his neighbours despite his house being extended unlike his neighbours'! This could cause a future potential buyer to worry unnecessarily what is wrong with it. But other than that it makes for interesting, and sometimes scary, reading.