There was an existential moment - I don't know if I want to call it crisis - when I turned 50 and I felt 'this is interesting; how did this happen?' It affected me in a way I wasn't expecting. It made me pause for reflection.

I prefer the simple things and I love walking in the countryside, or going camping... but simplicity is hard. It's easier to over-complicate things.

Riding a horse and using a phone camera is tricky but if you don't take pictures or record the moment, you lose it. You want to have a record of it.

I hate all those celebrity sculptures like Tussauds, where everyone is dressed in spangly suits and they are all smiling.

I met Amy Winehouse a few times and she was always funny, charming and self-deprecating - just a delight to be around.

I was asked to do an ad campaign for a supermarket once. I was baffled. It's strange when you realise your popularity or reputation is a marketable commodity; it's a stock, a currency.

When I was in Cardiff, playing with the National Orchestra of Wales, they said they get letters from people complaining if they're smiling during the concert. Nuts, isn't it? As if you have to respect the solemnity of the music by not smiling. Music is this joyful thing that enriches our lives, and you're not supposed to smile?

It's a lovely moment when everyone's part of something greater than the sum of its parts. That encapsulates what a comedy gig should be, with the comic as the lightning rod, the Norse mischief god, getting the audience to do something they wouldn't necessarily do.

But being in 'Doctor Who' is a dream come true. I've been a fan since I can remember watching TV.

You have to go to Scotland at all times of the year - in order to appreciate the times when the sun does come out.

A lot of the time, you need to find the right home for ideas. You know, sometimes you think 'oh this'd be a sitcom, oh, no it wouldn't, it'd be a drama, or an educational thing, or a doco or something.' I've got loads of ideas and you just have to keep sending them and pitching them.

You spend a lot more time on your own as an only child. And there's space to allow your imagination to take flight.

At school, I was bored with the teachers, and there were moments where I felt they were singling me out.

I don't think any comic could say there isn't a bit of them that doesn't want to show off.

You have to have a thick skin, yes. If you're going to do something as foolhardy as standup, you've got to be able to take it on the chin if someone has a go at you.

I quite like confounding people's expectations.

I think that generally there's a pressure to live the best life you can.

I'm one for new things: I like new technology, I like new music, I'm not entrenched in some view of what culture should be. I like the fact that it's constantly changing and that language is changing, that behaviour changes.

I think happiness really happens when you least expect it: it's when you're not really thinking about it, when you're not trying to achieve it, when you're not trying to get the perfect holiday, the perfect life, the perfect body, the perfect existence.

People are obsessed by how I look.

Twenty-two years I've been doing this comedy lark, so it's been like a meteoric rise to fame... if the meteor was being dragged by an arthritic donkey across a ploughed field, in northern Poland.

If you're going to perform, you're going to attract criticism. You can't please everyone all the time. You don't know how things are going to come out. But that's part of the fun of it, the adventure of doing any kind of art.

I didn't have any brothers or sisters, so I did a lot of stuff where I entertained myself playing games, reading a lot, a lot of fantasy novel stuff.

I think gaming has influenced popular culture in a huge way. It's worked its way into novels, and blockbuster movies.

When you're a birder, you have all sorts of reference books, and you know about migratory patterns and technical stuff. Most people just look out the window, and say 'is that a pigeon?'

Films and gaming are blurring together, and it makes for brilliant popcorn entertainment.

I play the piano and that's how I learned about music. I then taught myself the guitar, drums, percussion and various other things, such as the bazooka, the mandolin, the Theremin, the alpine horn, the didgeridoo.

The devil's in the detail and sometimes if you're thinking too big, you can miss the detail.

In 1994 I was doing a two-hander with Sean Lock in Edinburgh and there were more people in the cast than the audience. It was pretty grim, quite a chastening experience.

I've always been reasonably upbeat about most things.

I've always been envious of certainty, of people who always seemed to have a plan for their lives.

I hate getting ill, it irritates me so I try to stay reasonably healthy.

I've started doing Bikram yoga. You're in a boiling hot room, bending over pretending to be a locust, you can't do that at the gym.

I used to like beer, but it makes me feel slightly queasy.

I said to my wife that if I had enough money I'd have my arms lengthened. Slightly longer arms would be great.

I don't like labels. I have always fought against that as a stand-up.

There was something about stand-up that music wouldn't give me, which was my love of the spoken word and the mercurial tendency of language to respond to what happens to you.

My grandparents would have big, long arguments that were entertaining and that's where I first noticed, and was thrilled by, political discourse.

It's been Bill for so long people think my name is William, but it's not, it's Mark.

We live in the age of entitlement, as opposed to enlightenment.

If you become famous but haven't actually achieved anything, then your life has no real meaning - unless you're spectacularly shallow.

I'm really grateful for the fact that I have full artistic control over my career. I can choose what film or TV projects I'm interested in doing.

Great music and great artists create their own music and look and are not manufactured.

Some musicians are a bit humourless about their art: they lose sight of the fact that as well as exercising their muse, they're there to entertain.

Now, with the success of musical comedy like the Mighty Boosh, Flight of the Conchords and Bo Burnham, I feel vindicated.

I had this plan that David Byrne was going to come through the West Country one day, think, 'Who's that guy?' and ask me to go on tour with them.

I was always part of the end-of-term review at school. We would mercilessly mock any slight weakness in the teachers.

When you say 'Hello Wembley!' you're not just saying hello to a large shed. You're saying, 'Hello, I'm following all the greats that have played here before.'

I was asked to perform at the Olympics Opening Ceremony. But I was up a tree in Borneo filming a documentary about Alfred Russel Wallace! So it couldn't be done.

When the sun shines in Britain there's no finer place on Earth.