Qubes OS A Reasonably Secure Operating System ][ Subgraph OS Adversary resistant computing platform ][ Docker Containers
JumpCloud Directory As A Service ][ Antsle A Cloud In A Box ][ Edge Linux Virtualization and Containers for Your Private Cloud
Duck Duck Go A Better Way to Search Engine ][ Hangups Linux Console Client for Google Hangouts ][ IFTTT If This Then That
WTTR.in A fun, minimalist weather page ][ Haiku OS BeOS Inspired OS project for bevy of architectures ][ Postman Postman API Platform
Gemini PDA PSION-style handheld with Android and Linux support ][ Kali Kali Linux ][ RISC OS Open for ARM devices ][ Unraid Storage & Containers
Jitsi: An Open Source alternative to Zoom ][ Clockwork Pi: Minimalist, Cyber Punk-esque handheld/terminal][ Parrot Linux: Parrot Project's ParrotOS
KVM: Linux Virtualization ][ FVWM The FVWM X Window manager ][ Open Nebula Open Source Hypervisor ][ OpenBSD Secure, UNIX-like
AROS AROS Research Operating System : AmigaOS-like OS ][Mastodon][

The Jargon File Old School Required Reading