Megan & Liz: 21 Under 21 (2012)

Megan & Liz: 21 Under 21 (2012)

No. 14: Megan & Liz

Birthdates: November 21, 1992 (Both age 19)

Why They're Hot: Not since Mary Kate & Ashley has a pair of teen twins made such an immediate impact on the masses. Hailing from Edwardsberg, Michigan, fraternal twins Megan and Liz Mace started turning heads in 2007 when they posted a homemade video of their self-pinned song "This Note" to their YouTube channel. Five years later, the pair has racked up close 190 million views for their impressive cover videos, as well as their infectious originals. Not only has the pair's new single "Bad for Me" earned nearly 2 million plays since its August posting, they've sold more than 300,000 digital singles altogether, proving that the pair is a step above your averageYouTube phenom. With their debut album on the way next year, we're doubling down that 2013 will be nothing but good for these talented twins.

Video Below: Megan and Liz's "Bad For Me"

Next: Mindless Behavior