Have a look at the latest MOSS2007 Visio drawings for IT admins, this is really cool stuff:
SharePoint Database Administration
http://office.microsoft.com/search/redir.aspx?AssetID=AM101638931033&CTT=5&Origin=HA101639821033
SharePoint Application Security
http://office.microsoft.com/search/redir.aspx?AssetID=AM101638891033&CTT=5&Origin=HA101639821033
For those of you who don't have Visio....... http://www.microsoft.com/downloads/details.aspx?FamilyId=3FB3BD5C-FED1-46CF-BD53-DA23635AB2DF&displaylang=en
