Makumba helps you rapidly develop data driven web applications. Provides a custom JSP taglib as a main interface, but leaves API open for advanced access. It is implemented in Java.
Moved to GitHub: https://github.com/makumba
webOS is a web desktop environment offering a bridge between DHTML and PHP/mySQL using Ajax and JSON. It comes with a rich set of skin based UI widgets. The API is in javascript and its cross-browser.