Tired of typing in your super long and super secure laptop password every time your screensaver activates at home? There is a solution: dahoam. Dahoam is the Bavarian word for being at home.
Dahoam is also a Python based PAM extension which authenticates users if there is an active connection to a known WIFI network. This can be used by e.g. gnome-screensaver.
The (mini) project is hosted at Launchpad and can be downloaded here
Installation instructions are provided in the README file.
Update: Link to the 1.1 release which fixes a serious typo that broke the script.