Mindmapping and concept mapping (Score 1)

I've used info mapping techniques for a long time when I want to get my head around complexity - or even start thinking about a new project for the first time. There are dozens of software implementations. Here are some I know of:
3D Topicscape; Aviz Thought Mapper; Axon Idea Processor; BrainMine; Claro Concepts; Concept X7; ConceptDraw Mindmap; Conception & InterModeller; Freemind (SourceForge); Headcase; Hypersoft-net; I-Navigation; InfoPro (ZPAY); InfoRapid KnowledgeMap 2005e; Inspiration Software Inc.; jKSImapper ; LifeMap; Map it! ; Mind Manager; Mind Mapper; Mind Mapper; Mind Mapping Tool; MindChart; MindFull; ModellingSpace; MyMind; Novamind; Openmind 2; PersonalBrain; SoftNeuron Mindmapping SW; VisiMap Professional 4.0 (once called InfoMap Lite)
I have myself worked on a problem very much as described by sandbender, and did use ERwin as one poster suggested, but much later in the project. I started mapping out how all apps were connected, collecting info about the interfaces between all apps, who was responsible for each to have an overall picture first. Then worked up physical data model for each, and normalized them. Then I had a load of logical models. From that info, others went on to build an enterprise model.
dunno if that helps...