I use myrealbox.com for a mail list.

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MyRealBox is an Internet service based on Novell NetMail and eDirectory. The sole purpose of this site is to enable the NetMail engineering team to gain valuable information about how these products function in real-world high-volume situations. In essence, MyRealBox is a very large beta test site for NetMail. Many issues with NetMail are discovered and corrected through MyRealBox before they make their way into the commercially available product. Because of the testing nature of this site, service outages are to be expected from time to time as problems are discovered and diagnosed. We make every effort to minimize these outages; nevertheless, they do occur and are unpredictable in nature. After a service outage, the result is usually a more stable and better service.


Despite the warning, I have only had occasional problems, and then it is rare that everything isn't fine a few minutes later.


See also; Free Email Address Directory