This how-to explains the process of setting up a FreeBSD system that will act as a wireless router (as well as a wired router) that takes advantage of the ported version of OpenBSD's PF packet filter.
This tutorial is about wardriving using GPS. It explains how to install Garmin Etrex on Ubuntu and how to configure it. It also shows how to use Garmin with GPSDrive and how to convert the data to an xml file which can be imported by Google Earth.