The next innovation I expect to see on HN is a service that, on a set schedule, gathers articles about a set of topics that you follow, prints them out onto paper, and delivers them to you as a bound volume for easy perusal.
This has a number of advantages for privacy (there's no way for the publishers to know how much time you spent reading each story), offline-first availability (dead-tree is the ultimate), and sharing (you can hand someone the entire volume rather than just a link to it, and they get the whole contents, all offline).
It really sounds like it could be the hot new thing, if only some forward-thinking VC would invest in it.