I'd say that attention is the core currency of the individual.
You know, that perspective kind of makes sense, too.
It's connected to the other, in that attention costs time, but I can see this as having a certain truth. It also explains why there's a difference between wasting time (using it not to pay attention, or to pay attention to useless things), and using it well (paying attention to something useful).
In other words, attention can be used to add value to time that won't disappear after it has passed.