Aptana – Web IDE for Building Dynamic Web Applications
http://aptana.com/
Aptana is a robust, JavaScript-focused IDE for building dynamic web applications. Highlights include the following features: a) Code Assist on JavaScript, HTML, and CSS languages, including your own JavaScript functions; b) Outliner that gives a snapshot view of your JavaScript, HTML, and CSS code structure; c) NEW: FTP/SFTP uploading, downloading and synchronization; d) Error and warning notification for your code; e) Support for Aptana UI customization and extensions; f) Cross-platform support; and g) Free and open source licensed under the Eclipse Public License, v1.0. This has been added to World Wide Web Reference Subject Tracer™ Information Blog.

