I second this -- the Unix System Administration series (http://www.ocf.berkeley.edu/decal/2008-spring/advanced/ http://www.ocf.berkeley.edu/decal/2008-spring/ad

I second this -- the Unix System Administration series (http://www.ocf.berkeley.edu/decal/2008-spring/advanced/ http://www.ocf.berkeley.edu/decal/2008-spring/advanced/) and the DeCal classes in general were some of the most rewarding classes I took at Cal.