Following table lists the information about different screen readers:

Information related to the various screen readers

Screen Reader
Screen Reader Website Free / Commercial
Screen Access For All (SAFA) Free
Non Visual Desktop Access (NVDA) http://www.nvda-project.org/ Free
System Access To Go http://www.satogo.com/ Free
Thunder http://www.webbie.org.uk/thunder/ Free
WebAnywhere http://webinsight.cs.washington.edu/ Free
Hal http://www.yourdolphin.co.uk/productdetail.asp?id=5 Commercial
JAWS http://www.freedomscientific.com Commercial
Supernova http://www.yourdolphin.co.uk/productdetail.asp?id=1 Commercial
Window-Eyes http://www.gwmicro.com/Window-Eyes/ Commercial