http://lastwatchdog.com/driveby-downloads-lurking-8-million-small-ecommerce/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed:+LastWatchdog+(The+Last+Watchdog)&utm_content=Google+Reader
Interesting article on the dangers of not keeping software patched, particularly with regards to open source content management systems.
http://moinmo.in/
Wiki written in python as used by Ubuntu, FreeBSD, Debian and others. Uses flat file storage by default. Lovely.
http://www.gelatocms.com/
gelato cms is described as a tumblelog cms. It's based around the tumbr concept, you can easily post snippets. Various themes and plugins are available.
http://radiantcms.org/
Radiant CMS is a simple CMS system built in Ruby on Rails. It has a plugin interface so it can be extended.
http://www.weebly.com/
Create a web site and a blog on your own domain, for free. Powers Jessica Livingston's Founders at Work site.