Comments by Highlight - Collaboration on Highlight makes debugging faster than ever

Cusdis - Open-source, lightweight comment system for your website

Eccco - Record a listen short audios, like Twitter but with voice.

Comments for Zillow (Chrome Extension) - The fabled comment section on zillow

Email Comments - Add Google Docs like comments to Gmail

Localize - Localize is a no-code translation solution for SaaS platforms, allowing you to easily translate your web app, dashboard, API docs, and much more.