Forum Moderators: mack
It is difficult to recommend a particular CMS without knowing your specific needs (however, for a general portal site, I like Mambo Server).
You might want to check out [opensourcecms.com...] where you can put to the test a variety of CMS systems, then download the ones you like.
I use WebGUI by PlainBlack on a number of sites. It's written in Perl and uses MySQL - and has very friendly urls via use of mod_rewrite, plus one installation can server multiple sites. You can then set-up your web site users to be able to post content (articles, faqs, items or whatever - you decide what they'll have access to)
The software is a free download, but support costs - they also have a manual that is available for purchase (well worth the $) and active forums...
Hope this helps.
LisaB