SWTOR has a "Squelch" system. Basically if someone is spamming or posting rmt ads in chat you can click on their name and "Report" then a window pops up and you specify whether it's spam or RMT then that player gets put into a temporary squelch list for your account. If enough people report the offender then their chat privileges are revoked until their account is reviewed by someone.

How this game has made it this long without a right-click "report" function is beyond me, but the squelch system is also really nice, because then you don't fill up your blacklist with gibberish names that are going to be deleted in a week.