TextMate!

Notepad++ is a free source code editor and Notepad replacement that supports several languages.

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.

Brackets is an open-source editor for web design and development built on top of web technologies such as HTML, CSS and JavaScript. The project was created and is maintained by Adobe, and is released under an MIT License.

GNU Emacs is an extensible, customizable text editor—and more. At its core is an interpreter for Emacs Lisp, a dialect of the Lisp programming language with extensions to support text editing. The features of GNU Emacs include:

Smart PHP Code Editor

Text editor for the KDE desktop environment with support for multiple languages and syntax highlighting. It is extensible with plugins. Features a MDI interface.

Komodo Edit is a fast, smart, free and open-source code editor. Switching your trusty code editor is hard, but give Komodo Edit (or its big brother Komodo IDE) a try: it'll be worth your while.

Tool for building websites and applications. Adobe Dreamweaver software is intended for web designers, web developers, and visual designers.

Aptana Studio is a complete web development environment that combines powerful authoring tools with a collection of online hosting and collaboration services that help you and your team do more. Includes support for PHP, CSS, FTP, and more...

Coda is a fast, clean, and powerful text editor with pixel-perfect preview and a built-in way to open and manage your local and remote files. And a dash of SSH too.