Blocking spammers, what do you recommend?

Question

PHP

Good afternoon!
There is an idea to block spammers with a firewall, I found something similar, www.unix.ck.ua/content/blokiruem-spammerov-s-pomos...
but the parser does not work here... PHP is not strong :(
Perhaps there is a ready-made solution my question?

Answer 1

The best blocking of the rescue is Tarpitting (Tarpitting) - a delay in receiving a letter.
The spammer makes only one attempt to send the email - it does not repeat.
A normal server resends every 5 to 20 minutes.
You turn it on - you make white lists for mail.ru, yandex.ru and the rest - then you add partners - the rest will be slowly added themselves - there, if the letter is received, the server address goes into the white list for a week. There is nothing better in terms of efficiency - all spam lists - setting ratings does not work, but only crap.