Disqus offers the best add-on tools for site owners to power discussions, increase engagement, and earn revenue.
Many websites contain secret messages and comments. Imagine you could make these messages visible or even add your own. Now imagine that this function would exist everywhere and only the users themselves would have control over it. Wouldn't that be great?Discontinued
The last update is from January 2018, and the Chrome extension is gone.
An embeddable comment widget for websites, blogs, ecommerce & static pages. Joint Comments distributes JOINT tokens (erc-20 based cryptocurrency) to publishers based on the value of traffic.
It is free to use up to 250k page views / month.
A very fast, feature-full, and privacy-focused comment service for handling discussions on the internet. At 4.6 kB with no dependencies, it's the fastest comment service around.
LiveRe is an alternative to Disqus based in South Korea and used by LG, Samsung, Nike, Kia, Hyundai, ... Like Disqus you it allow social log-in. It allow comment with attachment such as image & video.