I can confirm that when I blocked a huge swathe of mobile broadband providers in Russia and Israel, something like 95% of the spam on the forum I run stopped in

I can confirm that when I blocked a huge swathe of mobile broadband providers in Russia and Israel, something like 95% of the spam on the forum I run stopped instantly. It seemed like a messy and obvious approach - sign up with a clearly bot-generated gmail account, hit the activation link sent by email an average of 100ms, and immediately post in every thread something along the lines of "WHEN WE'VE FINISHED IN KHARKIV / GAZA WE'LL BRING THE GAS CHAMBERS TO ENGLAND", all in under about ten seconds. I don't think it's Russians or Israelis behind it, necessarily, but that's where the annoying noise has been coming from.