I have suspicions about Orbit Downloader. I had played World of Warcraft for over 4 years with no problems and shortly after installing Orbit, my account got stolen and all my ingame items were sold off for virtual gold. I did eventually get everything back after a week and have since added an authenticator to the account but I still suspect Orbit of being a factor. I was using the full package of Comodo Internet Security at the time of the hack and got no alerts and I also never found any malware on the system by scanning with MBAM, SAS, Comodo's AV and since then Avast! How they got me is still a mystery.