A year and a half ago I wrote a LessWrong post on anti-akrasia that generated some great discussion. Here's an extended version of that post:  messymatters.com/akrasia

And here's an abstract:

The key to beating akrasia (i.e., procrastination, addiction, and other self-defeating behavior) is constraining your future self -- removing your ability to make decisions under the influence of immediate consequences. When a decision involves some consequences that are immediate and some that are distant, humans irrationally (no amount of future discounting can account for it) over-weight the immediate consequences. To be rational you need to make the decision at a time when all the consequences are distant. And to make your future self actually stick to that decision, you need to enter into a binding commitment. Ironically, you can do that by imposing an immediate penalty, by making the distant consequences immediate. Now your impulsive future self will make the decision with all the consequences immediate and presumably make the same decision as your dispassionate current self who makes the decision when all the consequences are distant. I argue that real-world commitment devices, even the popular stickK.com, don't fully achieve this and I introduce Beeminder as a tool that does.

(Also related is this LessWrong post from last month, though I disagree with the second half of it.)

My new claim is that akrasia is simply irrationality in the face of immediate consequences.  It's not about willpower nor is it about a compromise between multiple selves.  Your true self is the one that is deciding what to do when all the consequences are distant.  To beat akrasia, make sure that's the self that's calling the shots.

And although I'm using the multiple selves / sub-agents terminology, I think it's really just a rhetorical device.  There are not multiple selves in any real sense.  It's just the one true you whose decision-making is sometimes distorted in the presence of immediate consequences, which act like a drug.