WizTools.org RESTClient is the premier HTTP and RESTful WebServices testing tool. Written in Java Swing, and available in Apache 2.0 OpenSource License, it is one of the most comprehensive testing tool available.
The new version supports HTTP multipart requests, a tool to help in URL encoding / decoding (accessible from menu), and a quick response right-click pop-up menu to copy response cookies to request. Also available are minor bug-fixes and enhancements from previous versions.
Download from: http://code.google.com/p/rest-client/downloads/list