Using AT to schedule a command for later in Linux / CentOS

I know this should be one of those basic things ALL Systems Administrators knows but I just learned it today.  I just re-installed a  server with CentOS 5.2.  While it is mostly up to date there are a bunch of packages that need to be updated.  I didn't want to hog all of our bandwidth during production hours and I forget to do stuff once I get home, so I want this to happen with out me thinking about it too much.

From a command prompt I typed:

at midnight tomorrow [ENTER]

yum -y update [ENTER]

[CTLR + D]

 This set up my command to update via my Yum repositories tonight at 12:00:00am (well technically tomorrow).

That is all.