Notepad++ - A free source code editor which supports several programming languages running under the MS Windows environment.

OneNote - Get the OneNote app for free on your tablet, phone, and computer, so you can capture your ideas and to-do lists in one place wherever you are. Or try OneNote with Office for free.

Notepadqq - Notepadqq is a linux clone (identical application) of Notepad++

Simplenote - The simplest way to keep notes. Light, clean, and free. Simplenote is now available for iOS, Android, Mac, and the web.

Sublime Text - Sublime Text is a sophisticated text editor for code, html and prose - any kind of text file. You'll love the slick user interface and extraordinary features. Fully customizable with macros, and syntax highlighting for most major languages.

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.