Tumblr is a free blogging platform that takes about 5 seconds to setup. You enter your email, a password, and your subdomain, and your blog is instantly created. You can then build links to your new Tumblr blog and write content with anchor dofollow links back to your site.

I have a live Tumblr blog example for my Super Nintendo Console case study. You can see my Tumblr blog at super-nintendo-console.tumblr.com.

A good strategy to use with these free blog engines is to create a subdomain with the keyword you are getting, and then after you have added a good amount of content and a few links, use a few greyhat link building strategies to quickly index your new page which will help you get your actual site indexed quickly as well and without the risk of penalization.