GnuPG im Zusammenspiel mit Enigmail für Thunderbird ist nett, allerdings nicht allzu einfach zu installieren. Ich hab das Ding mal zum laufen gebracht.
Wer Paranoia hat und mit verschlüsselt mailen will (an mk AT php Minus homepage Punkt de):
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Version: GnuPG v1.4.1 (MingW32)
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