This is a good, basic guide to using graphics in most formal texts, including academic essays and reports. It's adapted from the hardcover book 'Power Tools for Technical Communication' by the same author. It was written in the 1990s, so the stuff on scanning is out of date, but the basics are sound.
A useful textbook about the basics of writing academic research essays. It covers similar ground to the recommended text by Grellier and Goerke, but with some interesting online examples.
Mindmiester is a fairly basic tool that allows people to collaborate on mindmaps. The free version is limited but the academic version is a lot cheaper than Mindmanager. There are also some good example of mindmaps.