If you ever looked for an open source alternative to your favorite application, then look no further:
Links:
[1] http://pulse.veltsos.com/category/it/open-source-foss
[2] http://pulse.veltsos.com/category/it/software
[3] http://linux.philosweb.com/drupal/files/image_2_95.png
[4] http://www.osalt.com/