Short applescript to toggle grayscale presentation on monitors (thanks, anonymous Better TouchTool user!)

grayscale.scpt

tell application "System Preferences"
	activate
	set the current pane to pane id "com.apple.preference.universalaccess"
	tell application "System Events"
		tell process "System Preferences"
			tell window "Accessibility"
				tell checkbox named "Use grayscale"
					click
				end tell
			end tell
		end tell
	end tell
	quit
end tell