*One thrust in personal productivity technology (to some degree precipitated by the popularity of this GTD methodology) is the development of location-based reminders. Your mobile device will sense (given your GPS reading) that you are at a hardware store, or at home, or downtown, and it will then alert you to actions tied to that physical environment. This makes sense in principle, but in practice, with all the variables involved and the desirability to overview our total inventory of actions from multiple angles, these will only be useful as a nice option to add to a rigorously managed list, as part of a totally reviewed and integrated system. Assuming this will keep your head clear and not miss something you’d want to see is still quite overoptimistic about that technology and its usage.