I’m not sure I remember who originally pointed this site out to me, but I’ve been recommending it to people for a good number of months.
OpenSourceCMS.com gives you the opportunity to try out different content managment systems of different types before you install them on your own server. It’s not easy seeing what a content management system might be like by looking at a site that uses it. It helps to see what the administrative side of the software does, too – how it is set up, how easy or difficult it may be to use, and so on.
At OpenSourceCMS, they include dozens of portals, blogs, ecommerce sites, groupware, forums, wikis, e-learning systems, and more. You can log in as an administrator, and make as many changes as you want while you are. Every four hours, they replace the software with a fresh version, and let people go back at it, testing the software out.
Even if you aren’t actively looking for a content management system, it’s worth spending some time at the site, and seeing what’s possible. There are also articles and forums, as well as user reviews of different CMS systems. If you’ve worked on web sites, but never used a content management system before, this is a nice place to learn about them.