I've been twice in a situation where I had to create a blog alongside a website. We've decided to externalize the blogging platform to wordpress.com (no maintenance and security concerns, good features, cheap, etc.).
I wish I could use an example.com/blog/ URL scheme, but it's not possible, so I chose blog.example.com.
I've been wondering how I could tell Google (and other crawlers) that those 2 are linked. There are rel="me" attributes on links, but it seems kind of thin.
Do you know any good way to "associate" 2 websites?