Accessing webservices via Javascript (aka AJAX)

Several times I've been asked, or saw the question on the newsgroups, how to create a piece of javascript code which retrieves data from a webservice. This information has been included in the SDK and you'll be able to find it here:http://msdn.microsoft.com/library/default.asp?url=/library/en-us/CrmSdk3_0/htm/v3d0accessingwebservices.aspHere's the code example of that page:// Declare