I always thought it would be cool to record audio the whole time the editor is open, and the programmer would just talk the whole time about his thought process. Then the audio would be broken up and indexed with the source code.
So you could choose to hear what the author was saying right when he was working on a certain area of the code. (You'd normally turn it off, but if you're really stuck it might be a good last resort.)
I do this with a notebook. When I'm coding I always jot down notes and thoughts. As long as you can remember the date when something was coded, you can see what I was thinking while writing it.
Has helped me figure out what the hell I'm doing many a time.
So you could choose to hear what the author was saying right when he was working on a certain area of the code. (You'd normally turn it off, but if you're really stuck it might be a good last resort.)