 guido a program that acts both as a pop client and a pop server you configure it by telling it about your real pop servers you then point your mail reader to the pop server at localhost when it receives a connection it connects to the remote pop servers reads your mail and gives you only the non spam fyi i ll never trust such a scheme i have no tolerance for false positives and indeed do nothing to try to block spam on any of my email accounts now for that reason deliver all suspected spam to a spam folder instead and i d love it 