Some great mini-posters for SharePoint 2007
Andrew May has some 17x11 posters he made (using Visio 2007 and its publish to PDF feature) that may be of use for you.
The first set deals with Content Types and can be found at:
http://blogs.msdn.com/andrew_may/archive/2006/05/26/SharePointContentTypesPosters.aspx
and the second set deals with SharePoint development and can be found at:
http://blogs.msdn.com/andrew_may/archive/2006/05/26/SharePointContentTypesPosters.aspx
I hope he makes more!