If you haven’t had to the chance to bone up on any of 2012’s biggest hits, you’ll appreciate a new mix by a so-called “DJ Earworm” who has crammed every jam of the year into one seamless track. From “Call Me Maybe” to Rihanna’s “Diamonds” to FUN.’s “We Are Young,” the top 40 melds into one poppy explosion. Mashing up tracks from hip hop, R&B and country (courtesy of Taylor Swift’s banger “We Are Never Ever Getting Back Together”), the four-minute Youtube video is a crash course in melody and of course, a perfectly executed earworm.