I was surprised to discover a service for bloggers called BuyBlogComments, which sell blog comments for around $0.25. What they do is look for blogs with a similar topic to yours that have do-follow links, and post a link to your blog in a comment or even comment in your name. Their service is quite expensive though. You will have to pay $25 for 100 comments, $124 for 500 comments, and $240 for 1000 comments. I would not use their service for various reasons. One of them is because I prefer to do such things myself rather than pay someone else for doing them. I think that in my case it would be a waste of money. The sad thing is that bloggers who will be tempted enough to use their service will have an advantage over other bloggers who post comments on other blogs by themselves. You will not find comments written in my name that are not written by me, and I do not believe that such service is ethically justifiable. Most bloggers would probably agree that posting comments in someone else’s name is not the right thing to do. However, I do not think that services like BuyBlogComments will cease to exist if they have a lot of customers.