On the Tuesday, Jan 5, 2010 edition of the TV show NCIS, the investigative team was dealing with Body Packs that can be used for individual flight.  I would imagine that the military is actually working on some form of individual flight device, but may not be able to share it.  I am sure there are a number of patents on different devices that persons have used to try individual flight packs.  What a great solution to traffic jams this would be, but on the other hand, it could clog the airways so badly that planes, jets and helicopters would be unable to fly.