For four days the trololo song has been stuck in my head. I can feel it lurking in the depths of my mind, ready to pounce and force me to sing it at inopportune moments. I fear for my sanity and the sanity of others. This song is catching and spreads like a virus. If it keeps spreading at this rate the world will never be rid of it. And why is this the case? This video right at the top there.