By making a habit of actually considering the things I can do, I think I can pick off that low-hanging fruit.
So you basicly want to prevent yourself from "doing X without having consciously decided to do so". (Doing X is not a problem per se, as long as it is a result of your conscious decision.) And the list of possible alternatives is there to increase the quality of deciding process, by considering more alternatives.
Perhaps there could be another part of this process: to consciously decide not only what to start doing, but also when to end doing it. Instead of evenings it could be better for weekends, when there is more time and more things can be done in sequence. -- Just because I consciously decide to start reading web in the morning, I don't want to stay online the whole day.
Some activities end automatically, such as watching a movie, where I just have to remember to make a conscious decision what next. For other activites, alarm clock could be used. (If this system works, it would be nice to have some socially acceptable invisible alarm clock that I could use all day.) I can set alarm to the time when I decide in advance to stop my activity; or if I don't know, just set it on one hour later to consciously decide whether to continue or stop. (It is possible to stop the activity sooner, unless for some reason at the beginning I decide otherwise.)
But it's better to start only with one habit at a time.
Important: The list of possible things should be in a visible place, to be automatically seen and easily used. (Avoid micro-obstacles.)
Background: I and many other attendees at the CFAR rationality minicamp last weekend learned a lot about applied rationality, and made big personal lists of things we wanted to try out in our everyday lives. I think that a regular (weekly or maybe semi-weekly) post where people mention any new interesting habits, decisions, and actions they have taken recently would be cool as a supplement to this; it ought to be rewarding for people to be able to write a list of the cool things they did, and I expect it'll also be interesting for other people to peek in and see the sorts of goals and self-modifications people are working on. Others at minicamp seemed enthusiastic about the idea, so I hope it takes off. Feel free to meta-discuss whether this is a good idea or if it can be done better.
Addendum 5/15: By the way, non-minicamp people should feel free to post too! I am highly certain that minicamp attendees are not the only ones working on interesting things in their lives.
This is the public group instrumental rationality diary for the week of May 14th. It's a place to record and chat about it if you have done, or are actively doing, things like:
Or anything else interesting which you want to share, so that other people can think about it, and perhaps be inspired to take action themselves. Try to include enough details so that everyone can use each other's experiences to learn about what tends to work out, and what doesn't tend to work out.
Discussion's likely to continue gradually through the week, so try to remember to check back now and then!