AMaViS: www.amavis.org

Cyrus IMAP 服务器和 Cyrus SASL: asg.web.cmu.edu/cyrus

Linux HA Heartbeat: www.linux-ha.org/heartbeat

IMAP Proxy: www.imapproxy.org

OpenLDAP: www.openldap.org

Postfix: www.postfix.org

Postal: www.coker.com.au/postal

SecuritySage: www.securitysage.com

Silicon Graphics, Inc. XFS: oss.sgi.com/projects/xfs

Spamhaus XBL: www.spamhaus.org/xbl

Spamity: www.collaboration-world.com/spamity

SquirrelMail: www.squirrelmail.org

tm: redbud.cats.ohiou.edu/tm