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Mashups have been a major part of Glee beginning with Vitamin D, the sixth episode of the first season (oddly, two episodes later, Glee aired an episode called Mash-Up, which didn't feature any). Since then, we've gotten Police paired with Puckett, Beyonce blended with Broadway and Madonna meeting Madonna.

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In the fourth season premiere (airing Thursday at 9 p.m. on Fox), Kate Hudson's character provides the first mash-up of the new year (Lady Gaga's Americano jumbled up with J.Lo's Dance Again) and it is one of the best the show has ever served up!

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But since that has yet to air, we can only look back in order to select the 5 Best Mash-Ups Glee has ever gifted us with!

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Song: It's My Life / Confessions Part II
Performed By: New Directions' Boys
Why It Works: Unlike the ladies' entry in Will's mash-off (Beyonce & Katrina and the Waves), these Usher and Bon Jovi songs seem to work off the same riff, and embrace the same anthemic aesthetic. LISTEN!

Song: Start Me Up / Livin' on a Prayer
Performed By: New Directions' Girls
Why It Works: In the season two rematch, the girls opted for Bon Jovi (mixed with The Rolling Stones) and emerged with a product that was more energetic, fun and memorable than the Supremes & En Vogue concoction the boys created. LISTEN!

Song: Get Happy / Happy Days Are Here Again
Performed By: Rachel Berry and Kurt Hummel
Why It Works: When New Directions' biggest most gay-friendly characters teamed up in Duets, tackling the iconic duet Barbara Streisand and Judy Garland performed (complete with era-replicated clothes) seemed rather obvious. But as Rachel & Lea Michele have proven over and over, she's more than worthy of walking in Babs' shoes! Listen!

Song: I Feel Pretty / Unpretty
Performed By: Quinn Fabray & Rachel Berry
Why It Works: The frenemys found common ground in season two's Born This Way, and this emotionally resonant mashup of West Side Story and TLC was the perfect expression of those powerful feelings. LISTEN!

Song: Rumor Has It / Someone Like You
Performed By: The Troubletones (ie: Santana Lopez, Mercedes Jones & Brittany Pierce)
Why It Works: Adele has been well-represented on Glee (Gwyneth Paltrow tackled her in season two, while tomorrow's season premiere features a stunning cover of Chasing Pavements). But the timing and meaning behind this particular mash-up made for an incredibly effective moment in the Brittana storyline. And you can never go wrong by mashing up the belting power of Naya Rivera & Amber Riley! LISTEN!

Check out Kate's contribution to the mash-up club and decide if it unseats any of the current Top 5!