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Maqetta is an open source project that provides WYSIWYG visual authoring of HTML5 user interfaces. The Maqetta application itself is authored in HTML, and therefore runs in the browser without requiring additional plugins or downloads. Maqetta is available under a commercial-friendly open source license. You can download the source code and install it on your own server, customize the code to fit your needs and/or contribute improvements to the open source project. The HTML pages created by Maqetta typically work across all popular browsers, including IE (caveat: this depends on the JavaScript toolkit you use and coding details). But if you want to run the Maqetta application, you'll need to use a recent release of one of the following browsers, all of which support the HTML5 features that Maqetta requires. The project's code is built using 100% open standards technologies.

openElement is a free website building application with a WYSIWYG interface ("What You See Is What You Get"). The software automatically generates the necessary code for a website to display and function correctly, without the creative constraints imposed by other tools. The benefit to users is a simpler approach for beginners and a faster approach to repetitive tasks for professionals. The concepts of "elements" and "packs" allow users to insert, modify, and customize commonly used web objects by simply dragging & dropping them onto pages - without writing any code. That said, users are not confined by the built-in elements: you can create, reuse, and share your own custom elements. openElement is a hybrid between a CMS and a standalone app. It really stands apart from other applications of its type. It works through an internal intermediary format that facilitates content updates, and maintains the structure and consistency of the resulting code.