It seems like there is a new "Hottest Pepper in the World" every couple of years or so.  Not too long ago it was the Red Savina Habanero with a Scoville heat rating of 577,000 units.  Now it is the Naga Jolokia (also known as the Naga Morris, Nai Miris, Bih Jolokia and Bhut Jolokia, etc.) with a whopping 1,001,304  Scoville Heat Units according to the New Mexico State University Chile Pepper Institute. In February 2007, Guinness World Records certified the Bhut Jolokia (aka Naga Jolokia) as the hottest pepper in the world.  It is reportedly called the "Ghost Pepper" because after one bite of the pepper you "give up the ghost".