cowsay
Cowsay is a linux/unix commandline program that prints ascii cow. You can define what the cow says and what kind of "cow" there is speaking. Cowsay has no real purpose, it's often used to mess around in chat programs like irc.
user@computer:~$ cowsay -f default Im a cow.
Prints the default cow saying Im a cow.
Prints the default cow saying Im a cow.