This summer he's back doing the day job, bringing last year's Edinburgh show Nunchuck Silver Medallist 2002 to London's Soho Theatre for a five-night run before taking it out on tour.
Ahead of the live dates, Digital Spy caught up with Joel to talk about martial arts, comedy, and just what happened when he tried to explain Pat Sharp to One Direction.
Nunchuck Silver Medallist 2002 - a great title, what's it all about?
"It's true to life! I was Nunchuck Silver Medallist in 2002. When I was a kid, I was obsessed with taekwondo but I was really bad at it. I found myself being really good at nunchucks, because I was such a loner.
"My mum used to call me 'My Little Ninja'. I used to head out into my garden and then I smacked myself in the back of my head with these wooden ones. I remember waking up on the floor, and my mum was stood over me and just said, 'I think my little ninja assassinated himself'."
Does the show include a demonstration of your skills?
"I wouldn't like to give away the end of the show, but yes it does! In fact I do nunchuks at the end of the show, in strobe lighting, to 2 Unlimited."
Is it a skill you've kept up over the years?
"No, but it is something you don't really lose. Before bikes were there, people were like, 'It's like nunchuks'. You don't forget how to do it."
You're skipping Edinburgh this year - is it a relief or are you missing out?
"I do feel like I'm missing out, I really, really do. But it's very nice to get more out of the show that I did last year. It's really nice to feel that everyone who wants to see it can see it... I was really proud of it."
Richard Herring has argued that comedians spend too much money promoting shows at Edinburgh - do you agree?
"Yeah, it's become a real monster. Comedians still use it for good - people still go, 'I really want to write a new Edinburgh show every year' - but people just spend more and more money every year, until the point where it's ridiculous. It's so ludicrous, how much money. The amazing thing is no-one knows about it! They have no idea that every show they see, a performer is doing their thing and most shows, 80% of shows, these people are spending £10,000 to be there.
"I don't know if it's ever going to change. There's other festivals now that are so good. Leicester's festival is brilliant, Glasgow's is amazing - it'll never take over from Edinburgh, but I think with Edinburgh something needs to change. It was a shame that Five Pound Fringe didn't work because that was perfect. People would go take a punt on a £5 show, but to go spend £12 on someone you don't know is quite hard."
Is your BBC Three show Impractical Jokers coming back for another series?
"I'm technically not allowed to say. But you know, obviously it is. It's ridiculous. We're all excited about it. Everyone loved it. It's one of the only shows I've done where unanimously 100% of people just properly enjoyed it. It's a real pleasure to work on so I'm excited."
As well as comedy you're also known for your presenting on MTV - does that get you any grief on the circuit?
"It's kind of fine. That's the nice thing about the comedy circuit - people only judge you on how funny you are professionally. I'm alright. I've been doing comedy way longer than I've been doing that stuff, so it's alright.
"MTV brought me in to be funny, so I came in and funnied it up a bit. I don't do anything for them anymore, so it's nice. Basically, right, what happened was, they let me go because they said I was too old. And I was like, 'I'm 27!'"
You're younger than me - that makes me feel even older!
"Oh God. Me and you both, we're both VH1 now."
I've started reading Mojo - I feel I'm drifting into middle-age fast.
"I've got a subscription to National Geographic! I interviewed One Direction, and this is one of the factors of me being too old. I interviewed One Direction and I mentioned the show Fun House, and they were like, 'What's that?'"
"I know, it's heartbreaking, right! Apparently when you're interviewing five of the most famous teenagers in the entire world for only three minutes, you are not allowed to spend two of those three minutes trying to explain to them who Pat Sharp and the twins are."
Has doing that job changed how you approach interviews from the other side?
"Yeah, kind of. I would never be rude or horrible anyway, but it just made me know what I don't want to be... people who just can't be bothered - it's your job!
"All you've got to do is sit there while people bring you fruit and say nice things about yourself and the film that you're doing. Just give me something! Just be nice, be courteous. People are such dicks, it blew my mind how rude people could be. But it also blew my mind how nice people were."
You did Made in Chelsea spinoff Live in Chelsea - what was that experience like?
"Amazing, really amazing. The Made in Chelsea lot are super nice. They're really lovely. They're very educated and know what they're involved in. They're very clever and they've all got their own little businesses now that are doing very well. They're lovely. There's a few duds! But most of them are all really nice."
Would you ever go on a show like Celebrity Big Brother?
"No, I don't think so. The good thing of being a comedian is it's always you... everything's an experience that you can tell a story about. I've done stuff where I've been like, 'I don't really want to do that', and you do it and you go, 'I'm going to get a good story out of this'."
"I did this Justin Bieber concert where they asked me to do ten minutes of stand-up comedy before he came onstage. It was mental - utterly mental. 10,000 people just going crazy and I just had to go and do stand-up - and of course they didn't want stand-up comedy! It was really fun in the end, it was just epic. I had to bring Reggie Yates up on stage. Everyone just going super-crazy.
"Then I had to run to town to do another gig. I was at this gig with 10,000 people, fireworks going off, Justin Bieber... then I had to go and do a stand-up comedy gig in front of 30 people that hated me. That's the brilliant thing about stand-up. If you feel brilliant it will make you feel s**t tomorrow."
You were in Skins a few years back as DC Sweeney - will you be tuning in for the finale?
"The trouble is I don't watch much TV because I'm working the time when all the good stuff is on... I watch a lot of box sets and stuff. I think it's a really good show. I think it's a generation-defining programme that people really loved and identified with and was really well-made.
"It's not very often that you get a show that's really well-written and well-made and looks really good. It was a pleasure to work on it. I still to this day, the more known I get doing comedy, people just go, 'I think I just saw you on Skins - what?!' I'm like, 'Yeah, yeah, I did that!'"
Joel Dommett brings Nunchuck Silver Medallist 2002 to the Soho Theatre for a five-night run from June 10-14. Tickets are available now.