If you're like me, you probably have a series of potential "sub-contexts" that are nested within your umbrella @computer context. These sub-contexts could be things like @code, @email, @web, @writing, and so on.

Even though you *do* all these things at the computer, it's likely that you have different mental contexts for each--especially for highly focused activities like writing or programming. It'd be way unproductive to keep jumping between writing code and writing emails. Your brain has to make a context switch every time you move from a @code NA to an @email NA, and you're losing valuable cycles.

If you've got a separate context for each mental context, you can sit down and say "okay, I'm writing this email to Sam... what other emails can I write?" or "I'm writing this article... what other articles do I need to be writing?"

The side effect, of course, is that you have that many more @context buckets that may contain a Next Action you'll be able to do at your computer. But by deciding on a sub-context: "I'm going to work on @code tasks for a few hours," you can filter that giant @computer NA list down to a much more bearable sub-list.

Also, if you've got a laptop, you've got two built-in subcontexts already: @online and @computer-anywhere. It's useful to have a separate list of things you can do at your computer when you're stuck on a plane with no web connection.