The ALTO Viewer
This is a simple Viewer written in PHP5 for the ALTO XML document format. It uses JQuery to allow the user to turn on and off the various layers which make up a basic ALTO document (PrintSpace, TextBlock, TextLine, String). It does not currently support the borders of the page although these should be trivial to implement in the future.
The code is hosted on GitHub:
And I have written a blog posting about the first release here