Agree with the recent comment links not working; I guess it's because of things being deleted from the comments section originally. (religion.blogs.cnn.com)
I don't even have any highly popular blogs that I author, but I still receive comments linking to casinos, computer products and other services. (capecodseo.com)
Categories could include article links, press release links, blog / blog comment links, directory links, industry / business profile links, social media links, and more. (searchmarketingstandard.com)