Achtung: a not very nice hotdog

lockit.sh

#!/bin/sh
#
# We have a few repeat customers here at the TWU 27 hotdog shack.
#
# They've decided it's FUN to visit our stand.
#
# So, we've cooked up something a little special for our valued customers.

set -e

osascript -e "set Volume 10"
say <<EOF
	ATTENTION!
	ATTENTION!
	ATTENTION!
	It was my responsibility to lock my computer when I was away.
	But I didn't.
	I could not even set my computer to automatically lock.
EOF

while ((1)); do
	say "OBVIOUSLY I HAVE MADE MISTAKES"

	# Invert the screen's colours.
	osascript <<-EOF
		tell application "System Events"
		tell application processes
		key code 28 using {command down, option down, control down}
		end tell
		end tell
	EOF
done