Nowadays, a capella groups like Pentatonix and Walk Off The Earth are topping album charts left, right and centre with original music.
But let's not forget that in the good ol' days - the Glee era, as we like to think of it - they all had to start somewhere, usually with a Disney cover recorded on a second hand mic and sheer determination.
We're kicking off the list with Pentatonix' main competition for Ultimate YouTube A Cappella Legend of Life - Walk off the Earth. (Yes, they have a guitar. So did New Directions, whatevs.)
We couldn't skip a cappella hero Jon Cozart, aka Paint, but we're being ultra hipster with the song selection.
Next is a legend, an OG if you will, of YT a cappella - Mike Tompkins. These days, Mike has quite a slick production going...
... but he came from humble beginnings.
And speaking of OG's... Remember when sweet musical angel Julia Nunes had, like, 4 million views with her cover of "Build Me Up, Buttercup"?
*In Chris Brown voice* Look at her now. Look at her now.
These days, the a cappella game is strong on YouTube with newcommers like the lovely celestial music child Julia Westlin (who needs more love, hello!)
And occasional dabblers like Trey Duffy and his crew. *WARNING*: Prepare to have your mind blown into outer space with inspo.
And one-woman choruses like Heather Traska...
But let's not forget that even chart toppers like Pentatonix had to start somewhere...