Jpowder v. 2.0 is downloadable from the 'Downloads' tab of this web site. For more information about this version of Jpowder see this publication: http://dx.doi.org/10.4236/jsea.2013.64021. Please note that this second version of Jpowder was not tested as much as it perhaps should have been. V. 2.0 demonstrates an example of 3D visualisation of multiple powder diffraction data.
Jpowder v. 1.0 is downloadable from https://code.google.com/p/jpowder/source/browse/JpowderWebSite/WebStart/Jpowder.jar. http://www.jpowder.org, and information about how to use this version of Jpowder see this publication: https://code.google.com/p/jpowder/source/browse/JpowderWebSite/Download/JApplCryst2010reprint.pdf.
Note, we used to host a separate web-site www.jpowder.org. We no longer do this and www.jpowder.org is now forwarded to this site. However, the out of date content of this web-site can still be reached from https://code.google.com/p/jpowder/source/browse/#svn%2FJpowderWebSite.
If the reader of this would be interested in taking this code forward in a new direction let us know.
Jpowder was originally a collaborative project between the ISIS Facility of the STFC Rutherford Appleton Laboratory and the E-Learning and Software Develepment Unit of the Kasem Bundit University. It later included a collaboration with Reading School of Pharmacy.