[Alfa1]

I do use a usergroup for new users, which they can only get out of if they receive 5 reputation points. That does work like a charm. Post count is something that spam bots seem to recognize, as they just start posting like crazy to get more than X posts. That caused me to put it the post count at 50. My staff catches them well before they can make that, as they are there around the clock.

I would expect that same about cookies, but I actually catch a very substantial number of spammers trough cookie. Happens every day.

Even after all of the above (including all of my suggestions and multiple account detection) we still get spammers, that try to circumvent the links block, in various creative ways. All these measures did get rid of 99% of all spam though, so its vital functionality for me.

To get an idea: I get 7.000 registrations attempts per month, of which 4.000 are successful and have confirmed their email and passed all spam checks. I have 3.000 banned members.