I mentioned Microsoft's new Open Source web site in the previous blog. So, it only seemed fair to note that Apple has had a site focused on Open Source for years. You can find it at...

http://www.apple.com/opensource/

The list the Open Source projects supported or used by Apple's client and server software. If you've never poked around your Mac, you may be surprised how many Open Source apps are pre-installed and ready to be used in Mac OS X.