FreeBSD
From Oracle FAQ
The FreeBSD project produces a freely available, multi-platform Unix like operating system for Intel compatible (x86), DEC Alpha, and PC-98 systems. It is based on the original Berkeley Software Distributions (BSD) code distribution.
Oracle support[edit]
Oracle Corporation does not officially support the Oracle database or any other of their products on FreeBSD. However, there is a vibrant group of users dedicated to making Oracle work on the FreeBSD platform. For some valuable resources, look at the external links below.
External links[edit]
Generic BSD and FreeBSD resources:
Oracle on FreeBSD resources: