Audio sounds
I seem to remember setting up an audio sound for the insertion of 3.5" floppy discs into an Apple Mac. Once the user inserted the disc the mac would reply loudly with a sultry female voice "oh, it's so big".
On windows machines we would set the startup sound to be of a noisy couple making love and then make sure the speaker volume was turned up high. Works great for female users who are more embarrassed than men.
Back in the old days of green CRT, you would turn the vertical position knob so that the command line was off the bottom of the monitor or turn the brightness way down so although it was powered up, no display was seen.