I've had a couple of goes now at setting up
Open Atrium - an absolutely gorgeous looking "intranet in a box" based on Drupal - and my advice for setting it up is...
1. Set up your (empty) MySQL database first
2. (Mac people) Unzip the .tgz file using Archive Utility rather than Stuffit Expander - the latter seems to miss out some files when it decompresses
3. Make sure your PHP memory_limit in php.ini is at least 64M. I tried to install with 16M = no go.
4. In sites/default, chmod the default.settings.php to 777, and then duplicate it. Rename the duplicate file settings.php.
I got number 4 wrong - I didn't read the advice quite right and wondered why Atrium couldn't set the database up. You need both files, the default.settings.php and settings.php.
There's some bonus numbers...
5. Make sure you pick Atrium from the selection screen at the start. (Look, this weissbier is pretty strong, you know?)
6. If it really really won't let you install the database, if it hangs at the database screen, you can edit the settings.php file, which should work...
Atrium is a version 1 (and a beta at that) but it looks pretty good so far. I thinking it's more in the
BuddyPress league rather than yer heavyweight corporate "enterprise" intranet software - this may suit, of course..