The concept of critical resource, robustly helpful in identifying other kinds of GTD Context can look suddenly inadequate when the main requirement of most of our work appears to be a screen and keyboard.

In these cases, I personally find it helpful to turn the concept inside out, and reframe it as 'critical constraint'. When I'm working at a screen, what are the 'resources' that most inhibit my work ?

For some tasks, for example, the resource that can be most usefully eliminated turns out to be network connectivity. Fiction is not, as it happens, my thing, but Jonathan Franzen's words still resonate:

"It's doubtful that anyone with an internet connection at his workplace is writing good fiction"

I am therefore naming and automatically restoring a set of different computing contexts, using Concentrate from http://getconcentrating.com/

In some of these named contexts, the key element is that certain applications and forms of connectivity are disabled rather than enabled. (Some of them, for example, launch Freedom for Mac from http://macfreedom.com/).

The names of the environments defined and saved by Concentrate match the names of the Mac sub-contexts which I use in OmniFocus. A draft script enables me to select a particular task/project in an OmniFocus window, and automatically launch the corresponding Concentrate 'activity', or computing context.

Once Concentrate has open/closed the specified set of applications, documents, connections, and web-sites, run any preparatory scripts, changed the desktop background etc, its timer is set either to a default for that environment, or to any estimated minutes setting which the selected task happens to have.

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