OpenJUMP is an open source GIS software written in Java. It is based on
JUMP GIS by Vivid Solutions. It's features include:

    * It is a Vector GIS that can read rasters as well.
    * OpenJUMP is known to work on Windows, Linux and Mac platforms, but
      should work on any operating system that runs Java 1.5 or later.
    * It is not just another free demo viewer, but you can edit, save,
      analyze etc. with JUMP / OpenJUMP.
    * It works, even with medium size datasets, and with professional
      touch.
    * It provides a GIS API with a flexible plugin structure, so that
      new features are relatively easy to develope around the sound 
      mapping platform.
    * It utilises standards like GML, WMS and WFS.
    * It is already translated in English, Finnish, French, German,
      Italian, Portugese and Spanish. The translation in other languages
      is in progress.

Extensions and plugins can be found at
WWW: http://sourceforge.net/projects/jump-pilot/files/OpenJUMP_plugins/

WWW: http://www.openjump.org/