JSXML
A set of JavaScript XML tools written with the goal of speed, simplicity, and minimal code. A parser that doesn't mind if you throw 2000 lines of (well-formed) XML at it, a unique builder that invites the coding of GUIs (graphical user interfaces) around it, and an iterator that makes costly recursion unnecessary. I've released it under the LGPL (it's free for private and commercial use, no strings attached).