Dynasty is a large graph browser that uses Dynagraph for layout. Dyna, a language and system for dynamic programming and natural language processing, uses Dynasty as its visual debugger. Dyna is led by Jason Eisner at Johns Hopkins University. Dynasty will be publicly available in early 2007.
An earlier attempt at huge graph browsing was Dinograph, whose code is still part of Dynagraph for Windows, but is no longer included in the binary distribution. Read about the proposed algorithm.
Dynagraph could be useful for mapping out browser history. Read about the tantalizing History Web and look at some screen shots.