Wordpress Post Navigator lets you view the posts of a blog hosted on Wordpress.com sorted by number of comments, number of likes, creation date. You can directly link the page with a blog domain as a parameter.
I was expecting something like Medium for WordPress: a feed of the top blog posts from all the blogs on WordPress, a curated aggregator.
This tool is especially intended for blog owners who, on wordpress.com, cannot show their posts sorted by number of comments or number of likes, which I find interesting metrics.