The simply the best collection of XML scripts
Seed-PHP is a microframework that offers you a really simple way to implement powerful RESTful APIs or even simple web sites that could support pretty much all needed methods and responses in JSON or XML formats.
A cross-browser JavaScript XML Library which includes basic functions and properties that Microsoft.XMLDOM ActiveXObject has. The purpose of the library is to solve the problem of creating different XMLHTTP and XMLDOM objects for different browsers. So you have only one cross-browser API.
A framework that takes in the XML file generated by Google Calendar and makes it PHP friendly. There are hooks that allow developers to loop through and generate their own themes outputting the necessary HTML.
A highly configurable jQuery autocomplete plugin. It supports local and remote data sets (JSON, XML and plain text), uses Ajax method calls, allows to search, sort and match the response phrase.