How to lock the screen in OSX

From day one of Mac ownership, one glaring omission has really bothered me.   There's no obvious way to initiate the screen saver or turn off the screen in order to lock the machine.  Locking the screen is a modern must-do in any environment.  Every other OS places this option in plain sight making it impossible to overlook.  With OSX, both options are obscurely hidden enough that no casual user would ever find them without Googling or mashing random key combinations for half an hour.

I'm here to tell you how to do both things.  First the easy one. To turn the screen off, effectively locking the machine, press Control + Shift + Eject on your Mac keyboard.  The more difficult trick is locking the screen by starting the screen saver.  Open up Keychain Access (hint: it's under Apps>Utilities) and choose Preferences from the menu bar.  Now check the box for "Show keychain status in menu bar."  You will now see a little lock shaped icon in the menu bar that allows you to lock the screen.