Fun trivia fact: Seth Rogan was actually hired almost right out of high school as a comedy writer on the Ali G show. He and his usual writing partner shared a salary. He was on the Howard Stern show a while ago describing the insanity of working with Cohen. Rogan described him as utterly fearless and was amazed that Cohen would NEVER break character...even in the face of real danger. There was an episode of the Ali G show in which Bruno goes to Florida for Spring Break and runs into some college guys partying. He gets them to do a bunch of goofy, homo erotic stuff (forming a human pyramid, wrestling with each other, etc.) then asks them to say hi to all their gay fans in Austria. At that point, they started chasing Cohen down the beach, threatening to beat the crap out of him. Rogan said that never once did Cohen break character the entire time, screaming like Bruno and shouting back at his pursuers in that goofy accent.
...sometimes I think Andy Kaufmann has returned in a different body.