coComment: my endorsement
If you leave a comment on a blog post and don’t want to keep checking back for any further comments, such as a reply to you by the post’s author, coComment is your friend. It’s certainly mine. While I have the post and its current comments on my screen, I click my coComment bookmarklet, and in the window that pops up I click “Track this conversation”. Any further comments will automatically show up in my feed reader. (Of course you can use it even when you haven’t left a comment yourself and just want to see what others are saying. I’m just focusing on what I find to be coComment’s prime benefit.)
I’ve been using coComment for around a year and I’d hate to be without it. I don’t see any obvious source of revenue, so I hope the people behind it come up with one. (Co-creator Laurent Haug wrote in My SHiFT talk: the lessons of cocomment.com that “Put the ads day one”, but I see no ads now. I rarely go to the actual site so it wouldn’t surprise me if the ads weren’t doing the job and were dropped.) I’d certainly be willing to pay for the service.