Oracle, Sybase, directory services, SAN, Quark/Adobe (entire enterprise print production solutions), full J2EE/Tomcat for web apps, etc. Don't forget, it is UNIX, which was running enterprise applications before Microsoft was born.
Not getting your point. I understand that Unix predates Windows. The discussion was about Macs. What's the point of running Oracle on a Mac, or Sybase, or anything else. What's your point?