Mecha Voice Mail
From Wiki
In this thread, U.S. metachatters created anonymous voice mail numbers with which to call one another. The numbers are listed below.
Note: This page is likely to be quite transient, since the mailboxes only remain open if there is activity on them by the box owner every 7 days. If you try to call a number and it is no longer valid, please update the wiki. And if you have a number, check it weekly to keep it active!