Since no one seems to have posted any messages about mail servers in the Software board, I thought this made more sense.

If anyone asks about POP3 or IMAP4 or WebMail servers, you can point them to the Mail Server Overview at "ServerWatch" as a starting point. Many of the reviews are out of date, unfortunately, with comments only on the upgrades and not a wholesale reconsideration of the product. Nevertheless, it was a lot more helpful than a general Google search for mail servers.

ServerWatch also has collections of reviews on web, application, news, ftp, chat, streaming media, etc., servers, which you can access at http://serverwatch.internet.com/servers.html.