I'm registered to run the Nike Women's Half Marathon in San Francisco on October 21. How cool is this - for folks who want to run 13.1 miles that same day you can register to complete the Nike+ Women's Half Marathon. All you have to do is register, use your Nike+ system and run 13.1 miles wherever you are on October 21. Upload your results before midnight and you'll receive an official finisher's key chain from Tiffany & Co, plus a (gender specific) finisher t-shirt. I don't have a Nike+ system (or an iPod nano for that matter), but I think this virtual half marathon is an amazing idea.