Here we have a list of software for different purposes that are (mostly) Open Source (and mostly free).

Software for creative & design purposes:

• Krita - Free and open-source raster graphics editor ~ equivalent of Photoshop
• Gimp - The Free & Open Source Image Editor ~ equivalent of Photoshop
• Scribus - Libre Desktop Publishing ~ equivalent of InDesign
• Kdenlive - Free and open-source video editing software
• DaVinci Resolve - Video Editing Software (not open source, but available for Linux)

Social media alternatives:

• Pixelfed - Image sharing app ~ equivalent of Instagram
• Mastodon - Microblogging ~ equivalent of Twitter. Have a look at the instances and choose what suits you best, rather than choosing the social.mastodon

Newsletter Alternatives:

• Listmonk - Self-hosted Newsletter

Text Editor

• Sublime Text

FTP, SFTP, WebDAV, and Cloud Storage Browser

• Cyberduck

Static Web Site Builder

• Hugo
• 11ty
• Pelican
• Jekyll

Cloud Suite

• Nextcloud

Hosting Options

• Cloud Cannon
• Codeberg Pages
• Gitlab Pages
• Netlify (free, but not open source)

CMS - Content Management System

• Tina

Digital Publishing Tools/Platforms

• Write Freely can be self-hosted and used for blogging, it has a (RSS) feed and can be published to fediverse.

Note Taking

• Joplin Can be self-hosted to use it across devices
• Cryptpad Online pad and online form (instead of Google Forms)
• Book Stack Collaborative note taking tool that can be self-hosted (actually a Wiki software)

Peer-to-peer File Sharing

• Soulseek - P2P file sharing, mostly for music

RSS

• Fresh RSS - Free, self-hostable feed aggregator

Ad-blocking

• Pi-hole - Network-wide ad and tracker blocking

Other tools

• Flying Carpet - Cross-platform AirDrop alternative