Sample page content
Download this template from http://www.microsoft.com/downloads/details.aspx?FamilyId=7C05CA44-869A-463B-84D7-57B053711A96&displaylang=en
See http://blog.spsclerics.com/Lists/Posts/Post.aspx?ID=34 for information on fixing a small bug to do with the tree view navigation on this template.
If you want to set this masterpage as the default for all new sites, check out this solution from Bill Baer http://blogs.technet.com/wbaer/archive/2008/07/03/master-page-example.aspx