jQueryPad
NB: Download link finally fixed
jQueryPad is a fast JavaScript and HTML editor. Just start it, enter the HTML you want to work with, bash in your jQuery code, and hit F5 to see the results. Say goodbye to ALT+TAB.
jQueryPad is xcopy deployable. It's written in WPF and uses the Web Browser Control to embed Internet Explorer for testing the script. When you press F5, the HTML and JavaScript are combined into one file and rendered. The template also references jQuery, so the jQuery functions are available.
If you want to use a different version of jQuery or reference other files, just replace the files in the Templates directory.
Hope you find it useful - feature suggestions are welcome.