It ocurred to me last night that there's useful information in some forms of comment and trackback spam. Largely, I find that I receive bunk responses in older posts… indexed posts… posts that must rank well in the search engines? Ah, so spammers are doing the research for me – and I think I can appreciate it. This isn't just lemonade out of lemons, though – this is exploiting their exploits. They know what they're doing – they know they're gaming the system. I wouldn't go as far as to say that every piece of trackback or comment spam will lead you to understanding where you sit in the search engines. But if you watch the patterns of your spam, you might find that some posts are attracting more junk than others.