As email spam starts to be brought under control by sophisticated anti-spamming software, legislation and prosecution the spammers are looking for new spam targets and they have found this in forums and blogs.
Spam bots trawl the net and now instead of collecting email addresses they are registering themselves on forums and blogs so that they can post new topics, threads and comments with links to their spam sites or products. Depending on the sophistication of these bots, they register multiple aliases and sometimes they lie dormant for several months before attacking - this fools the algorithms that watch newly registered accounts to see if they will spam and gets by the probationary period.
In the fight against spam on forums and blogs, the spam fighters have a slight advantage which they don't have in the email war. When a spam bot tries to register itself on a forum, and if it is identified as a spam bot, the forum can immediately fight back by making requests to the domain from which the spam bot is coming from and deny registration. (This sort of counter attack is not possible in email.) This will create a type of SDOS on the bot.
What is a SDoS? It's a new acronym I've just invented. Self Denial of Service - the counter attack to DDoS. The attacker is looped back onto itself.
In order for this to work the forums and blogs need to work together in order to identify domains and IP's that are hostile. This list needs to be shared and kept up-to-date. When a registration is attempted by a known attacker the forum or blog will redirect the attacker back to itself. Send it home without supper - so to speak.
Do you want to see this in action?
Try and register yourself with an email address of [email protected] (a known domain used by spam registrants) on the Emini Futures Forum. You will notice that instead of getting a friendly "check your email" message you will find yourself sent back to yourself and probably see an error page.
Of course this could just be wild fiction...