https://github.com/skeept/dotvim/blob/master/plugin/ZoomWinP...
Basically, if you have multiple split windows, it allows you to do a cmd+O to zoom the current split view (i.e. making it the only view visible). That's neat if there's something tricky going on (say a weird bug) and you want to focus just on this piece of code, without seeing anything else. Once you're done, you can hit cmd+O again, and your old split setup comes back. I love this plugin.