The OpenBSD project produces a FREE, multi-platform 4.4BSD-based UNIX-like operating system. Our efforts emphasize portability, standardization, correctness, proactive security and integrated cryptography. OpenBSD supports binary emulation of most programs from SVR4 (Solaris), FreeBSD, Linux, BSD/OS, SunOS and HP-UX.
OpenBSD is freely available from our FTP sites, and also available in an inexpensive 3-CD set.
The current release is OpenBSD 4.8 which was released November 1, 2010.
OpenBSD is developed by volunteers. The project funds development and releases by selling CDs and T-shirts, as well as donations from organizations and individuals. These finances ensure that OpenBSD will continue to exist, and will remain free for everyone to use and reuse as they see fit.Download it from here (32-bit):
ftp://ftp3.usa.openbsd.org/pub/OpenBSD/4.8/i386/install48.isoDownload it from here (64-bit):