Day after day, week after week, we continue to see new codecs released on the unsuspecting public. All I can do from the keyboard here is ask you to spread the word to your friends who like to watch videos.
Do NOT download codecs! If you do, you will end up with pop-ups and a balloon-type message telling you that your computer is infected, attempting to entice you to pay for their fake software.
The latest dumped on the unsuspecting are Moviecodec, tvcodec and watchfree. The are all fake codecs, ready to install trojans, and more on your computer.
See samples at SunbeltBLOG.