I find browsing hackernews to be one of the more beneficial activities I can do for 5-20 minutes as a break between more mentally taxing activities. Meditation, going for a walk, getting a snack or a drink, and a quick chat with a friend are other activities I consider both beneficial and short duration.
But I had, and I can tell from experience, it's the one Internet activity where I find it hard to determine its net value.
With anything else - TV shows, Reddit, Facebook, browsing memes - I can tell the marginal value becomes negative very quickly (after satiating the basic need to relax/unwind). So it makes sense to spend some, but only a little time on this.
But with HN... it feels like the above, except every other week I'll find some thought that will improve my understanding of the world. Every other month I'll find a tool that solves a problem or improves something in the projects I'm working on. Every couple years I hit something that essentially alters the course of my career. And around people I work with, I'm known to be the guy that, when told a problem, half of the time will point out a solution mentioned in some HN comment a year earlier (thank $deity for Algolia making finding it again easier).
So bottomline, I suspect the total net value of HN for me, after accounting for opportunity costs, is actually slightly positive. At least the procrastinator in me keeps saying that, conveniently omitting the confidence interval, which is absurdly wide.
