You’ve probably seen this yourself already if you’re running a blog yourself, but the referral spammers are now using referrer URLs that don’t have any DNS records yet, I presume because they think that people can’t check them out first to see if they’re a spammer or not.
Of course, it’s fairly obvious because how on earth do you get a referral from a site that doesn’t exist! They go *plonk* here as soon as I spot them..