<Tr> <Th> Known for </Th> <Td> Magic, comedy, skepticism </Td> </Tr> <Tr> <Th> Website </Th> <Td> www.pennandteller.com </Td> </Tr> <P> Penn & Teller (Penn Jillette and Teller) are American magicians and entertainers who have performed together since the late 1970s, noted for their ongoing act that combines elements of comedy with magic . </P> <P> The duo has been featured in numerous stage and television shows such as Penn & Teller: Fool Us, and they currently perform in Las Vegas at The Rio, the longest running headlining act in Las Vegas history . Penn Jillette serves as the act's orator and raconteur . Teller generally does not speak while performing, and instead communicates through mime and nonverbals, though his voice can occasionally be heard during their live shows and television appearances . Besides magic, the pair has become associated with the advocacy of scientific skepticism, and libertarianism, particularly through their television show Penn & Teller: Bullshit! . </P>

How long has penn and teller been doing magic
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