Singapore, Nashville, San Francisco, Incheon, Munich, Sydney, or Hong Kong. If you are flying through any of these airports, you should check out the entertainment available! For example, Hong Kong has an on-site cinema with an IMAX. If you have a delay, it would definitely be a great way to pass the time!
Get more info on the other airports at CNN.com or here: http://tiny.cc/ejb8uw