I&#x27;m really surprised there is no mention of SOGo (<a href="http:&#x2F;&#x2F;www.sogo.nu&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.sogo.nu&#x2F;</a>).<p>It has a nice mail interface plus calendaring and even provides mobile device integration via an Exchange compatible interface (so your mobile device calendar and email integrates using the Exchange connector).<p>I&#x27;ve never understood why it does not get more traction (or mention on HN).