You can deploy end-to-end solution like zimbra (community version is open source and free). Has all necessary features (DMARC, SSL, clamav, spamassasin, and s-mime), really good webmail interface, some "cloud" file storage features (briefcase!) and more. As more and more people depend on big providers like google and microsoft with they mail we should advertise as much as possible, and convert as many as we can to self hosted mail solutions. Mail is last bastion of free communication. And should last "neutral" as long as is possible. Big providers are bulling smaller ones marking mail as spam/junk or blocking entire address spaces on "we thing that we should, and we do as we thing" policy.