Forum!?

I was thinking about adding a Forum to my blog, but have questions on how it would work. I would like it to directly link this blog and be some what easy to use. In browsing the inter web for such free forum hosting sites I seem to have come up short. I was hoping that someone out there in the Blogger community might be able to help me out. I would like to keep it free since my blogging does not bring in revenue and it's something I do in my spare time, as of right now anyways. If you can think of any thing send me an email to lightsonanemptystreet@gmail.com or leave a comment. Thanks!