I have often wished for such a diagram for corporations or brand name ownership. Who owns whom, who spun off whom, etc. I enjoyed the micro-version of this idea for the music (entertainment?) companies that I saw posted on this blog many months ago.

Is there a particular set of technologies/software that works for the organization of such a project - aside from 4x6 cards, as Lombardi used - or are we in a "make do" mode with homegrown or glued together solutions?

-megan