For lectures, a mind-map might be a more appropriate way of keeping track of the relationships between ideas. Now, I’m not the biggest fan of mind-mapping, but it might just fit the bill. Here’s the idea: in the center of a blank sheet of paper, you write the lecture’s main topic. As new sub-topics are introduced (the kind of thing you’d create a new heading for in an outline), you draw a branch outward from the center and write the sub-topic along the branch. Then each point under that heading gets its own, smaller branch off the main one. When another new sub-topic is mentioned, you draw a new main branch from the center. And so on. The thing is, if a point should go under the first heading but you’re on the fourth heading, you can easily just draw it in on the first branch. Likewise, if a point connects to two different ideas, you can connect it to two different branches. If you want to neaten things up later, you can re-draw the map or type it up using a program like FreeMind, a free mind-mapping program (some wikis even have plug-ins for FreeMind mind-maps, in case you’re using a wiki to keep track of your notes).