knowledge representation

i've been thinking about planning and organization lately, especially with respect to innovation and creativity. i was reminded of this when i saw gentoo update freemind, a mind mapping program. five minutes of poking around on wikipedia turned up articles on concept mapping, semantic networks, and other things that look similar to the directed graphs i've started to use. i've been trying to find a way to represent dependencies and alternatives so that i can identify critical paths and distractions. maybe i should look into concept mapping and semantic networks for this. the knowledge representation category has a number of related articles.