Mendeley - Easily organize your papers, read & annotate your PDFs, collaborate in private or open groups, and securely access your research from everywhere.

Coastline - Simple minimalist text editor. Create, open, edit and save plain text files.

Zotero - Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.

Nebulous Notes - Nebulous Notes is a powerful, yet simple, text editor for note-takers, writers, and coders.

Qiqqa - Qiqqa is a free research and reference management software. It can be used in many organizational projects from the academic to the personal to the business endeavor. Read more about Qiqqa.

Jota Text Editor - Jota, pronouced as "i-o-ta", is a text editor designed for a long text file.