However, my reading habit is quite bad. In part, this is because I don't really know how to take my own ideas and move them to a more organized place (most of the time).
For people who read their own journal entries at a later point in time: what do you do (and why)? Do you categorize everything? Or do you just read it and that's that?
But I have discovered a really working way of using kind of external device for learning goals - I have a student who desires to learn anything I know on programming, he is probably a best way possible to refresh and debug my knowledge.
It's kind of like a wiki, except markdown based, and in a cross-platform application.
It's free as long as you don't want to use their cloud services, also.