cat -v should be a separate executable and not a command line option. That's the Unix way.
head isn't needed because we can already do it with the command line options for sed. That's the Unix way.
Hmm, it seems like I must write my own Master Foo koan (this is a first draft only, improvements welcome):
Master Foo looked up from his lectern.
"Greetings," said Master Foo. "Who are you?"
"I am the Master Planner," said the Master Planner. "Ninth of my dharma line," he added modestly.
"I am Master Foo," said Master Foo. "What do you plan for?"
"To reach enlightenment by concentration on a single focus," said the Master Planner. "Therefore I remove all that is unnecessary from my life."
Master Foo said nothing, but began to type fiercely. Those students who could see what he was doing were astonished that he appeared to be typing complete gibberish.
When he stopped typing, Master Foo pushed the device to the Master Planner. "Read me, if you would, the last maxim of the Zen of Python."
The Master Planner appeared as astonished as the students. "But all men know that the twenty-one maxims of the Zen of Python have been unchanged since the Master Sorter wrote them down long ago!" he protested.
"Nevertheless," said Master Foo softly.
The Master Planner gave the words of command and then spoke very softly. "It says -- it says, 'Inclusion is better than exclusion.'"
On hearing these words, all present were enlightened.