I've never had much of a problem with spam in comments to my blog posts, but lately there've been a few. None of them have made it past blogger's spam filter. They all seem to be from the same anonymous poster.
What do they think it accomplishes? Mine is not a well-read blog, so few people see the posts, much less the comments, much less the comments on years-old posts. So, even if the spam comment gets posted and even if I were to miss the email notification and the comment got to stay up and even if someone were to actually see the comment, i figure the chances of anybody clicking on their links is about the same as someone getting struck by lightning on the same day they win the big-money lottery. I suppose it could happen, but I wouldn't put money on it.
So why do they bother? Is this some automated process like recorded phone sales calls? It just seems like a waste of time on an endeavor with no hope of any return.