I use this whenever I need to scroll through all the existing groups on a server.  It's handy if a particular group happens to have hundreds of members and screen real estate is miniscule

# cat /etc/group | cut -d : -f 1 | less

Use this to create a tarball 4.7G at a time (perfect for writing to DVD) from the root "/" directory.

sudo tar -cv -M --tape-length=4928307 --file=concord_home_7_18_08-1.tar /home/concord

When prompted, create a second 4.7G file like this:

Prepare volume #2 for concord_home_7_18_08-1.tar and hit return: n concord_home_7_18_08-2.tar

Copy the files onto any new destination and combine them into a tarball which can be extracted normally using this:

sudo tar -x -M --file=concord_home_7_18_08-1.tar largefile.tar

Prepare volume #2 for concord_home_7_18_08-1.tar and hit return: n concord_home_7_18_08-2.tar

Prepare volume #2 for concord_home_7_18_08-2.tar and hit return:

Keep going until you get the completed "largefile.tar" then move it to the root "/" directory on the new hard drive and:

sudo tar xvf largefile.tar 

Get a list the files within the directory with the most recently accessed files at the bottom of the list

$ ls -ltur

Count the number of files you want to keep - then get the file count for the directory

$ ls -ltur | wc -l 

Delete the top 107 files from the directory.

$ for file in $( ls -ltur | head -n107 | awk {'print $9'} ); do rm -rf $file; done

Sometimes when I'm searching huge config files like those of Samba or Apache it's easier to skip past all the comments.

$ cat /etc/samba/smb.conf | grep -v \#    <-- hides all lines with # anywhere in them (even at the end)

$ cat /etc/samba/smb.conf | grep -v ^\#  <--  hides only lines beginning with #