The tldr is it maps urls to key words / phrases that we input. Those mappings go into a shared list, using the browser extension you can then search for them in the browser bar.
We tend to plow in tons of stuff, some of which we may never use, but countless times I've bashed in a phrase out of pure hope and found a team member or me in the past have added the resource in.
Lists are a bit like repos, you can have private ones just for you or you can share them, and they can all be searched at the same time.
It's a bit rough around the edges, but it's free at the moment for non-enterprises.