Notational Velocity - Notational Velocity: modeless, mouseless Mac OS X note-taking application
Milanote - Milanote is a note taking app for creative work.
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.
snipnote - Organize your day with tasks, notes & checklists
Notational - Notes at the speed of thought
Walling for Windows - Visual walls for your ideas and projects. Now on Windows.