I have to say, Gmail's spam filter is quite good, and even the very few that get through, once I mark them as spam, I never see them again.  I leave my spam folder alone, and the emails are deleted as soon as they are 30 days old, so I have a running monthly total of spam.  About a year ago, a spam king was taken down.  How do I know this?  Because one year ago, my spam folder dropped from 2000 a month to 1000.  Over the last year, it fell to 800.  Now, however, it's back up to 1000 again.  It started going up about the first week of January.  (I am very careful not to give my e-mail address to anyone who could spam, but sadly I had three other folks with my name give out my e-mail address as theirs, and the floodgates opened.)