After a year of trying to get a usable intranet with Drupal we finally bit the bullet and decided to use a custom solution. The problem is that we were trying to force Drupal to do what it wasn't designed for. Drupal, and many other open source content management systems are suitable for a single purpose organisation or department, but do not appear to handle multiple groups are purposes very easily. For instance, our intranet was both a news site and a repository of fairly static content. The area devoted to HR should be discrete from the science information. But Drupal's support for 'landing pages' was poor.
I'm sure that Drupal could be modified to cope with our needs, and I am equally certain that there are open source CMS's that can handle our intranet. The problem is that these CMS's often need grunty hardware, specific software or extensive customisation. We are limited with regards to the hardware that we have access to and moreover we are severly time and resource limited. I need to get a working intranet up in a matter of a month, in addition to doing all my everyday duties.
After looking at Plone/Zope and Microsoft SharePoint I decided to stick with my own solution: tincaCMS. I wrote tincaCMS for the ICT Centre's public website using PHP and MySQL. It's fast and, because I know the code, I can make it do what I want without trying to hack somebody else's code into a form it was not designed for.