====== alternative to spamfighter ======



====== list of addons ======


http://email.about.com/od/outlookspamfilters/Spam_Fighting_Tools_for_Outlook.htm

Outlook comes with a spam filter, but it is good, not perfect. There are many anti-spam plug-ins that claim they can do better, and some of them really can. Find them here.

====== list filtering ======

email filtering service

http://www.appriver.com/services/spam-and-virus-protection/index1.aspx


http://www.chacocanyon.com/resources/email-challenges.shtml


http://en.citizendium.org/wiki/Email_challenge-response

http://www.spamarrest.com/tryit/index.jsp?1339089174837


http://www.spamhelp.org/services/listings/challenge-response/


https://en.wikipedia.org/wiki/Challenge-response_spam_filtering


http://xeams.com/challengeresponse.htm

http://www.junkemailfilter.com/spam/working_with_our_competitors.html

http://www.google.com/postini/