cowsay is a silly little command line text filter that displays a cow saying (or thinking) whatever text you feed it. For example, each time I log into my server via ssh I am greeted by a friendly cow who gives me a random quote.
cowsay has a number of options that change how the text is displayed and the appearance of the cow (dead, greedy, paranoid, etc.). There is also a library of "cowfiles" - alternate pictures that can be displayed in place of the cow.
Some of the options available:
The -n option turns off word wrap. If it is specified, the given message will not be word wrapped.
The -W specifies roughly (where the message should be wrapped. The default is equivalent to -W 40 i.e. wrap words at or before the 40th column.
There are several provided modes which change the appearance of the cow depending on its particular emotional/physical state.
The -b option initiates Borg mode;
-d causes the cow to appear dead;
-g invokes greedy mode;
-p causes a state of paranoia to come over the cow;
-s makes the cow appear thoroughly stoned;
-t yields a tired cow;
-w is somewhat the opposite of -t, and initiates wired mode;
-y brings on the cow's youthful appearance.
The -f option specifies a particular cow picture file (``cowfile'') to use.
The -l option lists all the cowfiles available
If cowsay isn't already installed in your distribution, installing cowsay is a snap. Almost all distros include cowsay in their repositories, so its a simple matter of installing via your distro's package manager. (apt/Synaptic, yum, pacman, YasT, etc.)
In the event you can't find a cowsay package for your flavor of Linux, you can download the source tarball from http://www.nog.net/~tony/warez/cowsay-3.03.tar.gz and build cowsay from source.
Cowsay Homepage: http://www.nog.net/~tony/warez/cowsay.shtml