This is something I came upon very recently, that I have not read anywhere else. What I post here is probably the start of some cool new train of thought that will lead to a breakthrough for me.
In order to motivate myself to work, I relate the work to my core value on a moment to moment basis.
For example, for the longest time I procrastinated school work. I'd always get high grades on procrastinated work anyway, and I didn't really want to do it, so why bother? As I wrote in a Facebook note, procrastination has probably cost me more time and energy than any other practice of mine.
This is basically gone because I now relate my work, all of it, to my core values. I attach it and associate it to something that I am extremely passionate about.
In my case, it's learning and intelligence. I say to myself, "This action is me becoming more intelligent, more powerful (power), more aligned with destiny (love), more in tune with the world (truth)." I don't lie to myself; it's true. Doing my work does do all these things for me.
You can think of this as an enzyme-coupled reaction in biology. My passions, learning and intelligence, are exergonic reactions, releasing a tremendous amount of energy which is then coupled to endergonic reactions, those tasks of mine that require willpower, effort, or an input of energy. I do not just couple the reactions to things I love doing, but to things I need to do in the bigger picture. This is perhaps related to Steve's concept of scaffolding.
Since I love biology, thinking of it in this way proves effective in getting things done. Questions like "What can I do today to move me towards my goals?" and "What can I do today that would have the most positive leverage in my life?" naturally occur.
You can adequately use this by finding a topic of great interest to you and coupling the resistance-free energy you get from that to things you might not otherwise do.