GitHub's Explore Email
As much as I love GitHub, I think the exploration paradigm could use a little work -- it seems to have something of a flywheel effect, where popular repositories receive more exposure, thus more stars/forks/watches, thus appear as 'trending', thus become more popular.  (For example: currently trending as #3 in Python today is the official Django repository; and trending as #2 today is the official AirBNB javascript style guide, which has been boasting around 4,000 stars and hasn't been updated in around ten years.)I'd kill for a GitHub StumbleUpon: click a button (filtering for, say, vertical or programming language) and get transported to a repository that has a baseline level of merit (say, at least three stars).