4chan - 4chan is a simple image-based bulletin board where anyone can post comments and share images.

Moodle - Moodle is the world's most popular learning management system. Start creating your online learning site in minutes!

Reddit - Reddit gives you the best of the internet in one place. Get a constantly updating feed of breaking news, fun stories, pics, memes, and videos just for you.

Collaborator - Система дистанційного навчання повного циклу із аналітикою в реальному часі та інструментами внутрішнього маркетингу.

Tildes - A non-profit community site driven by its users' interests

Lessonly - Getting teams up-to-speed and keeping them there.