Help A Man Out

I'm stumped. There used to a syndicated radio talk show on in Dallas where the host would amazingly serve as not only the host but also the guest by changing his voice. It was pretty amazing in that he would have a conversation with himself but you'd swear there were two people involved. I know that sounds confusing, but it was good stuff. His basic schtick was to have his "guest" make outrageous claims to get unknowing listeners to call in. Question: Anyone know who that guy was? For the life of me, I can't remember.