I recently created a new plugin called the "Simple CMS Plugin". It is designed to convert the standard WordPress administration panel into a CMS suitable for basic static websites and is available here: http://ryanhellyer.net/2008/03/14/simplecms/
In concert with this, I have also released the "Simple CMS Theme". This is intended as a development theme for others to design their own themes for static websites.
The default themes which come with WordPress are (unsurprisingly) designed for blog use. However much of the functionality of those themes is not necessary for a simple static website, and so I have removed all of the extraneous stuff which is unnecessary and only left the bare basics to help newbies build from.
You can download it and see a live demo of it here: http://ryanhellyer.net/2008/03/14/simplecms_theme/
If you have any questions relating to the theme, then please leave a comment on the Simple CMS Theme page.
I retain the full copyright to the code, but encourage others to modify it to suit their own needs.