This is an acronym it means down wind travailing faster then the wind. There was a you tube video(Don't have the specific link.) that stated you can build a device that travels down wind faster then the wind. In other words it could create enough power from the wind, and make it's self go faster then it's power source. My first thoughts were it was a fake but throughout the video the testes he did made me think it might work.I have attempted to build it but.(as I am horrible with my hands in that respect)have failed. Check the video then respond I would like to know if this is plausible or just a hoxe. Here's the link http://www.youtube.com/watch?v=xHsXcHoJu-A