Tomboy - Apps/Tomboy - GNOME Wiki!
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
Turtl - The secure, collaborative notebook
Tyke - Mac menu bar app that @torrez really needed to take notes
Carnet - Opensource rich text note taking app
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.