I recently used these instructions to remove the "nofollow" tag on the comments on this blog! For those that don't understand, this essentially means that search engines like Google will crawl links in the comments, and thus it will increase the pagerank of any linked pages. My hope is that this will encourage an active following of readers and comment-ers on my blog and increase reader participation, as now you can get a little link love when you make contributions in the form of comments!
Now I do understand the risks of doing this. The original reason the "nofollow" tag was created was to curb comment spam, after all. However, I'm not too worried about this at the moment, as my blog doesn't get ALL that much traffic, and I moderate comments anyhow. Anything that is blatant spam or is simply a "Nice blog!"-with-a-link sort of comment will quickly get nixed. I encourage all of my fellow running bloggers to do the same with their own blogs, as it boosts the community as a whole and will actually encourage participation on your site.
You may also notice a banner I added to the left sidebar that proudly proclaims the "DoFollow" status of this blog!