1. Quanta plus
For quick and effortless web development - Quanta Plus is steadily becoming a worthwhile competitor to the commercial web editors on the market. Quanta Plus's features include multi-document interface, WYSIWYG (What you see is what you get) editing and templates. Among the advanced features your will find team development, plug-in support and a PHP debugger. The objective of the team behind Quanta Plus is simply to developer the best tool for web development.
SeaMonkey settles all of your internet application needs in own package. Its a web-browser, email and newsgroup client, HTML authoring program and IRC chat client all-in-one. In most areas - web-browsing and email/newsgroup support SeaMonkey is similar to the stand-alone applications Firefox and Thunderbird. The Composer is simple but yet powerful and handles tables, CSS and positioned layers.
Kompozer is an open source web development tool built on NVU. The project strives to fix bugs in the NVU project and added new features to it. Both the HTML editor as well as the CSS editor has so far be fixed and updated as part of the Kompozer project - and many more changes are scheduled. Apart from that the main feature set is exactly as in NVU. And one of the most important features is still that editing take place in WYSIWYG (What You See Is What You Get) mode allowing you full control of layout as you work with your web design.