If you do decide to run a blog, don't forget to tell everyone about it on the list of blogs thread:
http://www.babypips.com/forums/forex...highlight=blog
Wordpress, the blogging software, is free. You can have
WordPress host a free blog for you, or use a site such as YourForexBlog.
If you decide to host your blog on your own server, then you obviously need to pay for the domain name and hosting on that server (just as you would for any website). You can use WordPress for free after that. You obviously get a lot more control over things if you are hosting your blog on your own server, but it's more technical and not for everyone.