The Bat is an e-mail application that supports multiple POP3 accounts, multithreading, MIME and UUencode standards, multimedia, APOP authorization, and PGP. It features message notification, message sorting, message templates, and minimization to the system tray. You will also find a fast and comfortable message editor with text highlighting, as well as a mail dispatcher for managing messages on servers. English, Russian, German, Dutch, Polish, Swedish, Italian, Lithuanian, and Romanian interfaces are built-in, as is a multilingual spelling checker.
More info:
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