http://en.freestatistics.info/stat.php
http://statpages.org/javasta2.html
http://statistiksoftware.com/free_software.html
http://www.statsci.org/free.html
http://www.evaluation.lars-balzer.name/links/tools-free-no-cost/statistical-software/english-language/
http://gsociology.icaap.org/methods/soft.html