Useful apps

Creativyst: JavaScript Compressor, CSV to XML Converter, CSV to JavaScript, JavaScript Sandbox, Outlook to DCEvents.js


mafriedman: Web-based Javascript IDE

JSMin: The JavaScript Minifier

Ajax Toolkits

Interesting Open Source projects to make AJAX and XMLHttpRequest easy:
Dojo Toolkit
DWR - Direct Web Remoting
JSON-RPC-Java
Haven't had time to evalute and compare these projects. Does someone have an opinion?