For gaming's sake, I have been using Windows for the holidays. And I think one of the most useful keyboard shortcuts in Windows is the Screen Lock shortcut. Especially now that the laptop is within the reach of my very curious 3-year old boy's hands, I most often need to lock the screen when I walk away even for awhile if I don't want any of my "work" getting accidentally closed and unsaved.
Being a newbie with OSX, I find it surprising that a Screen Lock keyboard shortcut isn't built into Mac OSX. Of course, google could tell you a lot of ways in how to do this, but I find the following below to be the most natural and effective among all of them.
Steps:
1. Go to System Preferences -> Security
2. Verify that the "Require password ... after sleep or screen saver begins" option is checked.
You can set this with whatever setting you like but I would recommend setting it to "immediately".
3. Open Automator (Finder -> Applications Folder)
4. When Automator opens, it will let you choose a template. At this point, select "Service".
5. In the "Service receives selected .." option, select "no input" for the first option, and "any application" for the second.
6. In the left side is the Actions Library, drag and drop "Start Screen Saver" to right side.
7. Save and give this service an appropriate name.
8. Go to System Preferences -> Keyboard
9. Select the Keyboard Shortcuts Tab, and select Services from the list on the left.
10. On the right, under the General Category, you should see the service that you previously created.
11. Make sure that it is checked, and add a new keyboard shortcut.
That's it. You can try it now if you want. This has really been a great help to me.
Reference: Mac OSX Hints
