across our screens are numbered. how cool is the first lady. reporter: cool enough to run a potato sack race with jimmy fallon and now reached the finish line as the first lady of late night. her first talk show appearance featured her surprising people as they delivered farewell messages. to continue to go high even when the challenges of life make us feel low. thank you you so much. reporter: she was serenaded by steveie wonder who adjusted his lyrics. without further ado, we present the greatest hits of the comedy styleings of michelle obama. there was the he have lugs of