His most popular are sarcastic takes on Australian stereotypes, like a riff on the c-word that uses the offensive term so often it loses its meaning, or an ad for the Cowdownie Fair, a country fete which offers activities like back-shaving for dads and "paddock-standing" for $13 an hour. Those videos have racked up millions of views, and they've been so successful Williamson has turned them into a successful stand-up career which sees him perform in New Zealand for the second time next week.
His latest show is called Dumb Things I've Done, and Williamson says he has no shortage of material for inspiration. "I've done a lot of dumb s***. I'm telling a few stories, horrible text messages I've sent, things I've seen or maybe done once and never done again, that kind of thing. I'm a very honest person, I pride myself on it. I'm willing to say it even if it embarrasses me."
His live shows are much more personable than his videos, with Williamson incorporating many of his other talents, like "darker, cruder" Flight of the Conchords-style songs and behind-the-scenes photos, videos and outtakes.
"You become a personality online, I deliver my ideas but they're performed and acted out. Online you don't know who it is - it's just a character. With the stand-up it's more me, it's a bit more honest; you get to see who I am. People don't really see that through the videos."
Williamson says while on tour he is often approached by fans wanting to repeat some of his most famous lines.
"People get blown away, like they've just seen a ghost. People just say, 'Look it's this c***'. The word 'c***' is the thing I get quoted at me the most, and it means I get some funny looks from strangers."
Success means he's been too busy to make his YouTube clips lately - he's constantly on tour, and just finished shooting a zombie movie, playing a character written expressly for him.
But as his latest show proves, he's not afraid to embrace his humble beginnings.
So, what exactly is the dumbest thing he's ever done?
"There's so many I've never stopped to think. One time I licked 200 envelopes that were actually the ones that stick without licking, and I almost died Seinfeld-style. That's the dumbest."
Who: Aussie comedian Alex Williamson
Where: His new show Dumb Things I've Done, is on May 14 and 15 at SkyCity Theatre in Auckland, and May 16 and 17 at the Hannah Playhouse in Wellington.
Online: See his videos at on YouTube here.
- TimeOut