Install for Unix/Linux.
I wish I could tell you to just type in:
apt-get sabnzbd
but the situation is not that easy yet.
Detailed instructions for:
Assuming you have the Python 2.4 or 2.5 package already installed, you need to install a number of Python modules.
Often you can install these using apt-get commands (check your system's documentation).
cheetah-2.0rc7 or later
elementtree (1.2.6 or higher, but only for Python-2.4.4)
yenc module (0.3 or higher)
feedparser (4.1 or higher)
Additional packages for post-processing
unrar (3.6.6 or higher)
unzip (5.5.2 or higher)
par2cmdline (0.4 or higher)
Additional packages for Secure NNTP and Secure Email.
pyOpenSSL (0.6)
The next step is to unpack the SABnzbd.tar.gz file and install it somewhere appropriate. You don't have to be a system admin to install SABnzbd itself. It's just a bunch of text files (Python sources and HTML files).
You start SABnzbd.py from the command line (check if the X bit is set, otherwise do "chmod +x SABnzbd.py" first).
./SABnzbd.py
SABnzbd will startup and will try to find a web browser to show you its web interface.
Install as a Unix daemon
See : Install as a Unix Daemon