As an FYI some Usenet servers do a fairly good job of filtering sporge. I'm guessing Google Groups hasn't put a lot of energy into filtering.

sci.crypt seemed to be the main group under attack, with many sporge runs x-posted their, or with trolling having follow-ups set their. That made it easy to filter (if you weren't in sci.crypt) by killing anything xposted there.

Other recent runs seem to be not x-posted there. Sucks for people with news readers that can't filter properly, or for people with news servers that don't provider enough headers for decent filtering to be done.