Taco (@tacoapp), a side project of mine with Troy Davis, is a productivity tool that aggregates tasks across multiple services, 'from Asana to Zendesk', to help people stay focused. We're currently in the process of dogfooding a new Chrome extension that brings up Taco every time you open a new tab. This has proved to be an extremely effective way for us to remain focused. Since hitting 'cmd+t' inherently shifts your context, it's way too easy to get distracted and fall into the rabbit holes of Hacker News/Reddit/Facebook or any other social time-consuming vices. With Taco instantly showing up when opening a new tab, it becomes a gentle reminder for my remaining Asana tasks and GitHub issues that I had set aside to work on for the day. This helps me keep my focus and continue plugging away.
One issue we quickly noticed, however, was that seeing all of our tasks each time we opened a new Chome tab was a bit, well...daunting. To remedy this, we decided just the short list of 'up next' tasks would be appropriate to reduce noise and stay within our mantra of 'peaceful productivity'. So after some quick design iterations, we came up we came up with what we've been calling 'focus mode' - a simple and minimal way to toggle the visibility of your 'for later' tasks. Either clicking on a toggler on the left side of the screen (shown in gif above) or by hitting the keyboard shortcut '\' (same shortcut that hides files drawer on GitHub's Atom editor). Also state is saved via cookie so if you collapse and refresh, it will still be collapsed. We're still making small tweaks but we'll be rolling this out to all of our Kickstarter backers soon!
Oh, and on mobile (or slim screens), we simply just hide the toggler via CSS Media Queries: