I mean they [ Bradley Cooper, Zach Galifianakis] are both just really good guys and also they're both extremely funny in very unique ways. We made each other laugh an awful lot, and that goes a long way. And we also went through some hard times. I mean it was hard to make this movie [The Hangover].

I was just fooling around with the piano and Todd [Phillips] was like, 'Hey there's a great spot in the movie [The Hangover] where we need a little bit of a breath in the narrative. You should write a song and stick it in there.' And I was like, 'Well, what should the song be about?' And he said, 'The tiger.' 'Oh, okay.' So I went off and I wrote this song. I came back and Todd and I tinkered with it a little more and then we shot it right then. It all happened in a day.

Going into editing when I got to New York was part of that. I guess I just kind of wanted to know as much as possible. But I have a real love of the whole process, from start to finish. So right now, I fit into the acting part of the process, but I wouldn't rule anything out. I'm enamored with how the whole thing works.

I think that music at inappropriate times with inappropriate volumes can be the funniest thing ever.

We spent six weeks there [in Vegas]. The only thing crazy that I did was shoot that movie [The Hangovers]. The stuff in that movie is way crazier than anything I might have done, drunk one night in Vegas. I mean we did it for real in the movie, so that's as crazy as it got.

To be totally candid, it was really born out of a panic attack the summer between my sophomore and junior years, when I realized I wasn't going to graduate in four years unless I somehow managed to glue together all the courses I'd taken. That said, I'm really glad I did it, 'cause it was really fun, and I was able to just take whatever the hell I wanted.

I mean they [ Bradley Cooper, Zach Galifianakis] are both just really good guys and also they're both extremely funny in very unique ways. We made each other laugh an awful lot, and that goes a long way. And we also went through some hard times. I mean it was hard to make this movie [The Hangover].