In general, I find heuristics for focusing my attention other than where it falls naturally to be interesting only as novelties - soon I'm back to paying attention to whatever strikes me.

Same here. In daily life I don't find this much of problem but I sometimes regret that when I have to choose between for example TVTropes or something else, TVTropes usually wins.

I can entertain time-consuming meditative or introspective exercises to the extent I hope that I'll gain some permanent, low-maintenance benefit, like learning new information that will be useful without constant recitation, or forming more effective habits (in behavior or what I attend to).

One way I found to form habits is to try to change the environment in such a way that the habit you want to learn is also the path of the least resistance. If that isn’t possible, you can try to make it so that you pause and give yourself time to consciously make a decision instead of executing your old wrong habit routine.

For example, I usually hibernate my work laptop. After a couple of weeks however my ram usage tends to go to 2 Gb and stay there (not in the least thanks to visual studio & firefox with +100 tabs) and everything is starting to feel sluggish.

A reboot usually helps but I strongly dislike interrupting my work to reboot so I don’t do it much and, unfortunately, hibernating is always quicker then shutting down when leaving the office. So when I leave, I don’t have much incentive at the moment itself to shut down.

My solution was simply to schedule a batch file to run every Friday afternoon that disables hibernation (and another batch file to enable it again on Monday morning).