GMime GMime suite provides a core library and set of utilities which may be used for the creation and parsing of messages using the Multipurpose Internet Mail Extension (MIME).
Price: $GPL, Rating: 9, Downloads: 356
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Spruce Spruce is an X11 mail user agent (commonly known as an email client) written with the Gtk widget set.
Price: $GPL, Rating: 8, Downloads: 556
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