Apple has launched a new 1 billion song countdown to celebrate the historical digital music milestone. Apple's iTunes Music Store is offering a free 4GB iPod nano and a $100 iTunes gift card to a lucky winner who downloads every 100,000 song as well as a grand prize package that includes a 20-inch iMac, ten 60GB iPods, and a $10,000 iTunes gift certificate. "We’ve got one billion reasons to celebrate, and we’re starting with you. As we mark our way to one billion, the music fans who download every 100,000th song will receive a prize package featuring a black 4GB iPod nano and a $100 iTunes Music Card." In addition, Apple today lowered the price of the 512MB and 1GB Shuffle and debuted a new 1GB iPod nano as well as added Showtime content to iTunes. The website is offering a countdown image that shows a near-realtime count of the number of songs sold through iTunes and Apple said it will create a full-ride scholarship in the winner's name to a world-renowned music school. In addition, iPodNN notes a new utility that conveniently tracks sales of iTunes songs in the menubar.