MyEclipse is a software package for the Eclipse platform. They have a nice range of application and language bases. This includes Eclipse AJAX / Web 2.0 Tools. The tools themselves are very well done and offer a great plug in solution for the developer. The Eclipse Plugin
can be reviewed and downloaded right away!
Several other comparable applications I have seen range in the hundreds to thousands of $$ but MyEclipse is only running at about$30.
Take a try for yourself with their free download trial of the Eclipse Plugin