Page block diagram
I found a nice diagram in this paper on Why Your Website Needs Information Architecture.

They call it a page block diagram (I know I've seen something like this before) and describe it thusly: "Page block diagrams show an information architecture at the user’s level. This diagram is one of several we created for different content areas of the CogNet site. The diagram shows the structure of a journal article abstract page with a complete map of its links to other parts of CogNet and to external Web sites." Nice--like a wireframe but better.

