I like mind-mapping and I appreciate Freemind as a mind-map editor!
I have come to a point where I would like to have one map but be able to switch between different "views".
Imagine you have a certain problem - you put it in the centre and put various possible techniques (their names) how to solve the problem around. Next, you add nodes as components of those solutions, i.e. you draw a structure map, map nr. 1. Then you would like to depict how each of the solution actually works (function map, nr. 2). Another thing would be pros/cons of each solution (comparison map, nr. 3) etc.
Of course, you can have all of it in one picture but it becomes messy quite fast. It would be fine to have the map with layers - e.g. switching like in GIMP and with these features:
* solid nodes common for all layers
* nodes and connections which would be layer-specific
* easy way of drawing simple maps for complex problems
* simple form of 3D map
i'd also like to see this feature in freemind.