This was a verry educative read

My advise to you is this: when commenting on others blog, don't comment the conventional comment such as: nice write up, good work, interesting work, and cool etc. Comment something related to the subject matter of the post, let the authors know that you went through their work and lastly, let your comment be interactive, let it be something that will create a conversation between the authors and you the follower
The reason for the advise above is that, conventional comments are can be commented by anybody, even without going through the author's works. Always be different in what you do!

this was the killer for me. It pays at times to actually go through some post and make a nice comment. I saw a guy that made $19 just by commenting on a post.