Probably doesn't prevent the granting of a patent, however it makes it impossible to enforce the patent. Mike and I published this in 1998 http://www.rage.net/wireless/wireless-howto.html . A Cisco legal team found this in 2008 and contacted me because the owners of patent #7035281 were coming after them. Doing a simple write-up of what I thought was obvious at the time - stick a wireless card into a Linux PC and have it route packets - may have saved all of us from having the wifi router in everyone's home restricted by patents. So whatever ideas you implement, be sure to blog about them and make sure archive.org gets a copy.