When your printer is out of black
ink and you need to print something for
class, you print it in the darkest shade of blue and you
hope your teacher won't notice.
That shade of blue is called printer blue.
"My printer ran out of black, and I had my
mid-term
paper due tomorrow"
"What did you do?"
"I printed it in printer blue, I
hope the T.A. doesn't care"