JSitor - Test your NodeJS, JavaScript, CSS, HTML online with JSitor code editor.
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.
CodePen - A front end web development playground.
Standard Notes - A safe place for your notes, thoughts, and life's work
JS Bin - Sample of the bin:
Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.