MailTester.com Save
Online tool to test an e-mail address. Find out if is valid, why it bounces or what type of mailserver the mailbox is on.
http://mailtester.com/   

Mark's Apology Note Generator Save
Generates E-mails for you to send.
http://www.karmafarm.com/formletter.html   

Postini Save
In-line infrastructure for pre-processing email messages in real time. Allows email management applications to be integrated into any SMTP email system.
http://www.postini.com/   

Slugmail Save
An email based reminder service.
http://www.slugmail.com   

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