Some Free and Open Source Alternatives
Libre Office - https://www.libreoffice.org/
A free and open source alternative to Microsoft Office. Libre Office is capable of reading and writing to Microsoft Office Formats (among others).
Linux Mint - https://linuxmint.com/
Free and open source operating system. Does what Windows does without all the backdooring, forced updating and sabotaging of older PC's. Runs on most laptops and desktops with a far smaller resource footprint than Windows 10 (the earliest version of Windows still supported by Microsoft.
Reaper - https://www.reaper.fm/
Reaper isn't actually open source, although a lot of the JS plugins are and the scripts editable. For audio buffs, Reapers has the same capabilities as Pro Tools, Logic and Cubase (in some areas even better) at a fraction of the cost and a fraction of the resource footprint. More JS plugins can be found on github.
Shotcut - https://shotcut.org/
Great free and open source video editor. It has a load of excellent filters, really nice workflow, handles just about every video format you can think of, does chroma-key (green screening) and all that good stuff.
Mixxx - https://mixxx.org/
Free and open source software for DJ's. Mixxx is powerful, easy to connect and easy to use. it supports up to four decks and handles cueing and beat matching. It has the ability to change the tempo of songs without affecting the pitch and can loop four, eight or sixteen bar segments.
Transmission - https://transmissionbt.com/
Bittorrent Client that won't fill your computer with unwanted browser extensions and shitty programs without your permission. Simple, light on resources and free of the crap that installs with other torrent clients.
DEMOSCENE AND RETRO
https://www.pouet.net/ - Demo archive.
https://demozoo.org/ - Demo archive.
https://aminet.net/ - A set of interconnected WWW and FTP servers hosting freely distributable Amiga software.
https://www.araknet.xyz/ - CYBER CULTURE, TEXTMODE ART, RETRO GAMING & HACKER CULTURE.
https://plus4world.powweb.com/ - Commodore Plus/4 software archive.
https://flashparty.rebelion.digital/index.php?lang=es - Annual demoparty.
https://defcon.org/ - Annual hacking conference.
https://spacehey.com/home - Faithful reproduction of the original myspace interface.
https://eab.abime.net/ - The English Amiga Board.