For an individuals it's overkill buy at work we use something like this : * We use Google/Gmail only for mail hosting, not for calender or cloud storage. * Go

For an individuals it's overkill buy at work we use something like this : * We use Google/Gmail only for mail hosting, not for calender or cloud storage. * Google apps with our domain. * We have also an account at Yandex. * DNS service from DynDNS, MX ttls set to 3600 seconds (1 hour, it could be less) * For virtualization, we have a i7 machine with 2x1 TB disks (Raid-1). * For webmail, calender, sharing etc we use Zimbra ( open source version ). * Everyone has an internal email ( x@office.domain.com ) and external gmail account. Zimbra syncs itself with gmail. * When somebody sends email , depending user, zimbra send it using gmail or relay. * At 3 a.m. system automatically shut down Zimbra , takes backup on usb 3 hdd (~100Gb, arround 40 mins) and brings up it again( I know, there is a room for improvement, like rsyncing /opt/zimbra directory ). We change usb disks everyday or two and store other disk at somewhere outside the office. So, - If Gmail "dumps" us, we can change our MX to Yandex, stuggle couple hours and then continue to work. - If local server burns, users can continue to work using Gmail while we build & install new one. We tried rackspace email hosting but it had problems ( some mails doesn't delivered, some incoming mails lost etc ). Fastmail was/is expensive comparing current infrastructure and it could be viable if we have more than 30 persons. P.S. : I'm not saying this solution is perfect or it's the only way to do, i'm just sharing.