This greasemonkey script removes all messages posted by applications to your homepage. It gets rid of messages about quizes etc, basically all messages from any applications created by external developers. Just leaving messages from the original facebook apps such as status updates, wall posts, links, notes, photos, etc behind.
To install this script you need to be using Firefox, then you need to install the GreaseMonkey add on.
To install the Facebook Purity script visit the following site and click on the “install” button on the top tight. http://userscripts.org/scripts/show/44459