A modifier key is a key that when held in combination with another key, causes a unique behavior. For example, Command-c copies highlighted data to your clipboard. The Finder modifier keys are pretty well documented. But a number of menu items support modifier keys as well. For example:
- Click on the Dropbox item in your menu, you’ll be able to see the status of files that have sync’d as well as a cogwheel with the typical settings for an app like Dropbox. Option-click on the Dropbox menu item, you’ll see the items under the cogwheel menu.
- Option-click the Wi-Fi menu item to see extended Wi-Fi information.
- Option-click Bluetooth, you’ll see version and MAC address information for your bluetooth interface (note that the extended options are usually greyed out/informational).
- Option-click on the sound menu item and you can switch input and output devices (these extended options are actually shown as you can switch between things).
- Option-click AirPlay and you get, well, the same menu. So not all support extended information and options.
- Option-click Go to see Library.
- Option-click the Menu menu to see shift modifier keys to access All options (this actually works on a lot of menus such as Finder, File and Edit, but even within some apps).
- Option-click on the Notifications menu item and you disable Notification Center.
But my favorite, for Apple apps, if you command-click on items, you can just drag them out of your menu. This saves you from firing up System Preferences and unchecking the box to remove them from the menu.