While Wikipedia is the broadest unified body of knowledge, WikiSuite - https://wikisuite.org is the most comprehensive and integrated Open Source enterprise solution. According to https://wikisuite.org/License : "All Software Components are released under an OSI-approved license. Please see each component page for the specific license." - https://wikisuite.org/Software-Components
It can be installed in a similar way the YunoHost uses, on a fresh Debian 10 server, but it would be really awesome to be installed from YunoHost, using the apps already packaged.
Scribe - https://scribe.rip/faq is an alternative frontend to Medium.com so "Why Would I Want to Use This?". There are a number of potential reasons: 1 - You believe in an open web; 2 - You believe more in the author than the platform; 3 - You don't like the reading experience that Medium provides; 4 - You object to Medium's extortionist business tactics; 5 - You're concerned about how Medium uses your data; 6 - Other reasons. License available at https://git.sr.ht/~edwardloveall/scribe/tree/main/item/LICENSE .
YouTube has an extremely invasive privacy policy which relies on using user data in unethical ways. You give them a lot of data - ranging from ideas, music taste, content, political opinions, and much more than you think. By using Piped - https://github.com/TeamPiped/Piped/wiki/Instances , you can freely watch and listen to content freely without the fear of prying eyes watching everything you are doing. License available at https://github.com/TeamPiped/Piped/blob/master/LICENSE .
Farside - https://farside.link/ provides links that automatically redirect to working instances of privacy-oriented alternative frontends, such as Nitter, Libreddit, etc. The Farside's links work with the following structure: farside.link/<service>/<path>
This allows for users to have more reliable access to the available public instances for a particular service, while also helping to distribute traffic more evenly across all instances and avoid performance bottlenecks and rate-limiting. The license is available at https://github.com/benbusby/farside/blob/main/LICENSE and you can test the demo redirects at https://github.com/benbusby/farside#demo
Hashbase is a public peer service for Dat archives. It provides a HTTP-accessible interface for creating an account and uploading Dats. It was created to power a content-community for the Beaker Browser. The license for the source code is available at https://github.com/beakerbrowser/hashbase/blob/master/LICENSE and a demo website made with TiddlyWiki and hosted with Hashbase is available at https://tromsitegr.hashbase.io/#:HOME .