Fighting malware and spam

http://www.virusbtn.com/resources/spammerscompendium/index

Research at Microsoft

http://research.microsoft.com/en-us/

formerly the Conference on Email and Anti-Spam

http://projects.csail.mit.edu/spamconf/

To test list of MX records for a domain in priority order

http://www.mxtoolbox.com/

IP Subnet/CIDR Calculator

http://aruljohn.com/ipcidr.pl

Use websitetrafficspy.com and check traffics and visitors of any site

http://www.websitetrafficspy.com/

BladeAOLEmailRecovery

http://www.bladeforensics.com/video/BladeAOLEmailRecovery.asp

http://wordpress.bladeforensics.com/?p=83