Walk Off the Earth + Julia Nunes + The Mowgli's

Canadian quintet Walk Off the Earth has amassed a mint's worth of YouTube clicks with—what else?—its quirky covers of pop megahits, such as a version of Gotye's "Somebody That I Used to Know" in which the whole band plays the same guitar simultaneously. It's a cute enough shtick, but we're a little skeptical about how it'll translate to the stage. Opening is another YouTube sensation: ukulele-toting chanteuse Julia Nunes.