Technology analyst Bill Thompson has been getting lots of comments on his weblogs, unfortunately most of the want to sell him Viagra. He has been "flyblogged".
Earlier this week I got an e-mail to tell me that someone called Levitra had commented on one of my entries on the VoxPolitics weblog.
Online equivalent of putting ad for "private massage" on your coat
Since it's a group weblog for "e-democracy titbits and crumbs", we get quite a few comments from random readers, and often they are useful and informative, so I read it with interest.
Sadly, it was not about the latest e-voting disasters in California - a topic of great interest to me - but a rather obvious piece of spam.
It said; "Interesting comments and a Superb Web Site" and then, like so many spam e-mails, had a link to a site that wanted to sell me a Viagra alternative.
Over the next few days I got 20 more, most offering Viagra substitutes but one featuring a cable TV scam - presumably for the times when I would have used up all my Viagra supplies.
Every one of them was posted as a comment on the blog, and they could only be removed individually through the administrative pages of the site, which takes ages.
It felt like the digital equivalent of flyposting - coming home one day to find your windows covered with posters for dodgy clubs and bands you have never head of.
Although the term flyblog has been used already to mean either blogging about flying, or blogging while flying, I would like to claim it for the practice of posting spam comments to people's blogs like this: I have just been comprehensively flyblogged.
A quick online search revealed that the problem has been around for a while, but until recently it was largely done by individuals who would visit blogs and post their adverts, along with a link to whatever dodgy website they were promoting.
It had not happened to any of the sites I am involved with, so I had not noticed it or heard about it.
Now, however, it seems to have been automated: some clever programmer working for one of these iniquitous outfits has written a tool that goes around a list of weblogs and collects information on the various posts made to it.
It then creates the right HTML to fool the blogging software into thinking that a comment has been entered, and the resulting advert is posted to the blog as if it was legitimate.
That would explain why my colleague and fellow VoxPolitics poster James Crabtree is now getting 20 to 30 of these spam comments a day, reaching the point where he no longer has the time to remove them.
What is worse, there is no obvious way to block these posts without putting serious obstacles in the way of those who have legitimate comments to make.
Asking people to register before they post comments, or making them validate their comments by sending an e-mail and waiting for a reply, just get in the way. Building blacklists of sites that flyblog will be as ineffective as attempts to blackmail e-mail spam.
Blogs evolved out of a desire to remove barriers to online conversation, and restricting their ability to add comments would seriously reduce the sort of lively debate that makes them so interesting.
Perhaps the worst thing about flyblogging is that it is not covered by any of the spam laws that I am aware of, and probably is not illegal under data protection or hacking laws.
After all, a public blog with an accessible comments page is hardly a closed system, and even if you have an acceptable use policy saying what sort of postings you welcome, that is not legally binding either.
It is hard at first to see why the spammers are doing this. I am unlikely to be reading the comments on the latest mobile voting trials when I suddenly come across an advert for vicodin and feel so interested that I click on it.
One theory is that the real target is Google. A spammer's site with lots of references in well-indexed blogs will have a higher Google PageRank, so that anyone foolish enough to actually go searching for the product will find the spammer's site.
It is an interesting, but as yet unproven, hypothesis.
Whatever the reason, it is moving from a minor to major irritant. None of the other blogs I contribute to or run has been affected yet, but I can only assume it is a matter of time before the spammers move in, as they did first with UseNet and then with e-mail.
It depresses me to think that any open medium can be so easily undermined by people with no scruples, no sense of responsibility and no idea of the damage they are doing.
It also feels a lot more personal and intrusive than e-mail or UseNet spam.
A blog is a place to express your views in a public arena, and having some unknown people fill the space with advertising is the online equivalent of finding that someone has pinned a card advertising "private massage" to your coat when you were not looking.
I feel quite upset by this, and angrier with the spammers and their lack of respect for the principles of online co-operation than I have been for years.
Bill Thompson is a regular commentator on the BBC World Service programme Go Digital.