QOwnNotes - QOwnNotes is a free plain-text notepad with markdown support for Linux, Mac OS X and Windows, that works together with ownCloud Notes.
Atom - At GitHub, we’re building the text editor we’ve always wanted: hackable to the core, but approachable on the first day without ever touching a config file. We can’t wait to see what you build with it.
EncryptPad - EncryptPad is an application for viewing and editing symmetrically encrypted text.
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.
Notepads - Notepads is a modern, simple yet powerful text editor for Windows 10
Notepad++ - A free source code editor which supports several programming languages running under the MS Windows environment.