1. "Use Somebody," Scala & Kolacny Brothers View this video on YouTube Via youtube.com This soft, sweet piano and choral arrangement makes Kings of Leon's rock anthem sound like something straight out of Downton Abbey. 2. “Baby One More Time," Bowling for Soup View this video on YouTube Via youtube.com Britney Spears' bubblegum debut gets a brand new attitude in this darker, punky remake. 3. “Hot in Herre," Jenny Owen Youngs View this video on YouTube Via youtube.com The folk singer shows her fun side by taking on Nelly's sexy-fied hip-hop romp. 4. “I Knew You Were Trouble," Walk off the Earth View this video on YouTube Via youtube.com These quirky Canadians love putting their unique spin on pop songs. Here they take on Taylor Swift with a damn fun a cappella arrangement. 5. “I Will Survive," Cake View this video on YouTube Via youtube.com The disco anthem made famous by Gloria Gaynor has been covered countless times, but Cake's angsty version… takes the cake (ha!). 6. “Girls Just Want to Have Fun," Corey Monteith View this video on YouTube Fox / Via youtube.com The late Glee star broke all kinds of barriers by singing this stripped-down version of Cyndi Lauper's '80s hit to encourage a character on the show to accept her sexuality. 7. “The Scientist," Aimee Mann View this video on YouTube Via youtube.com Aimee Mann manages to make Coldplay's heart wrenching ballad even more intense in this live cover. 8. “Silly Love Songs," Darren Kriss & The Warblers View this video on YouTube Fox / Via youtube.com Glee hit a high note when it introduced the Dalton Academy Warblers in season two. The all-male a cappella group's interpretations of modern classics, like this version of Paul Mcartney & Wings' hit, offered something fresh and different for viewers. 9. “How You Remind Me," Avril Lavigne View this video on YouTube Via youtube.com Whatever your feelings are about Avril Lavigne and Nickelback, you can't deny that this version of the band's debut hit is certainly different. 10. “Holiday Road," Matt Pond PA View this video on YouTube Via youtube.com The theme song for the National Lampoon's Vacation movies by Lindsey Buckingham still holds up today. This quieter version by Matt Pond PA comes off the band's Christmas album. 11. “Of the Night," Bastille View this video on YouTube Via youtube.com Corona's "Rhythm of the Night" was arguably one of the defining songs of the '90s, and Bastille's darker version is still catchy as hell. Bonus: there's even a brief callback to "Rhythm is a Dancer" by Snap! 12. “Can’t Get You Out of My Head," The Flaming Lips View this video on YouTube Via youtube.com It's The Flaming Lips. Singing a Kylie Minogue song. Need I say more? 13. “Wishin’ and Hopin’," Ani DiFranco View this video on YouTube TriStar / Via youtube.com Ani DiFranco took a break from her usually politically driven folk songs to record this hit made famous by Dusty Springfield in 1964. DiFranco's version was used in the opening credits of My Best Friend's Wedding. 14. “Fix You," Straight No Chaser View this video on YouTube Via youtube.com The all-male a cappella group have a penchant for making fantastic vocal arrangements of pop songs (as well as some original stuff), and this Coldplay cover is proof. So many feels. 15. “Little Boxes," Walk off the Earth View this video on YouTube Via youtube.com Malvina Reynolds' satirical folk song got a new lease on life when it was used as the opening theme for the first few seasons of Weeds. While the show used numerous covers, this one is the best. 16. “Hey, Soul Sister," Darren Kriss & The Warblers View this video on YouTube Fox / Via youtube.com This a cappella version manages to capture all the crazy, mind-numbing joy of Train's original. 17. “Space Oddity," Natalie Merchant View this video on YouTube Via youtube.com Natalie seems to be channeling a little bit of David Bowie for this live cover. 18. “Rock Lobster," Seth MacFarlane (as Peter Griffin) View this video on YouTube Fox / Via youtube.com OK, so it's not a full cover, but I bet the B-52's would be proud.