You probably already have, and regularly use, one or more of the following blogs:
These social blogs encourage you to share - when you sign up for them, and as you use them.
Like Blogger they're all free to use.
They're great, but beware!
...because the (often personal) information you supply when you sign up for them contains invaluable data. It's recorded, as is everything we do online, and used by advertisers, organisations, government bodies and the like.
Be mean about the personal information you give away.