Working towards forest/chicken/island/vacuum protocol browser in Emacs (quasi mind-mapping):
artist.el in GNU Emacs
With functions such as:
(artist-draw-line 10 10 10 50)
(artist-draw-ellipse 50 50 20 20)
... circles, rectangles, figlet text.
related:
http://cedet.sourceforge.net/cogre.shtml
COGRE is pronounced similarly to cougar. It is a base library for editing and manipulating connected graphs. Additional tools will be available using COGRE for managing diagrams for UML flavors, such as a class hierarchy diagrams.
The short term goal of COGRE is just to be able to create and manipulate a few boxes linked together with lines in an Emacs buffer.
[ unrelated but also note use of doc-view for PDF viewing, and graphviz-dot-mode.el for diagramming ]
From Berlin Alexanderplatz [Epilog], Rainer Werner Fassbinder
das huhn besteht aus dem äusseren. nimmt man das äussere weg, bleibt das innere. nimmt man das innere weg, bleibt die seele
[after Godard: Vivre sa Vie:
A chicken is an animal with an inside and an outside. Remove the outside, there's the inside. Remove the inside, and you see the soul. ]
See also; sheep/island protocol.