I have become almost reliant on a great FREE mind mapping application, Free Mind

It allows you to hyperlink to other nodes, to other pages, to external files and sites.  I found it extremely useful when I studied for the GARP FRM exam.  For exams,  you can create an overview node with the main topics of the curriculum and then break out in detail a new page per subject.  Related topics can hyperlink between each other, then you add links to youtube or PDFs.  It really helped me.