The BBC news site had an article about a french website that puts you in touch with your neighbours;
The idea is that you sign up, answer a few questions about yourself, and you and your details appear on a map. Your neighbours can then get in contact if they want to, and local events can be announced etc. It looks like an internet dating site, but without the dating, if that makes sense.
It already seems incredibly popular, and in my neighbourhood there was already loads of people signed up. I didn't totally understand the questions that I was asked, so my responses were a bit lame - perhaps if I put some effort into it I could meet some people from around here which might be nice (my user name is TrickyNicky if you want to hunt me down). In the picture above, I'm the red balloon, and it seems that I live on a very dull street, since I'm the only one signed up. Well, that's one way of looking at it, the other way could be that everyone on my street has a life and doesn't need to sign up to sites like this :-)