Workflowy - A better way to organize your mind.
Source Wireframe Kit - Library of 537 blocks for desktop and mobile prototyping
Dynalist - Dynalist is a web app that lets you break down and organize your thoughts in the format of lists.
Contra Wireframe Kit - Open source wireframe kit for design and prototyping 🚀
SuperNotecard - Introducing SuperNotecard. SuperNotecard is an online writing tool that features virtual notecards to help arrange facts or scenes, track details, organize paragraphs, and clarify your composition process.
Platforma - Wireframe library of layouts and UI elements