Quickly Sleep the Display in Mac OS X with a Hot Corner

You can quickly sleep the display of a Mac or immediately start a screen saver by setting up Hot Corners, which are activated just by sliding your cursor into the specified corners of the screen.
Setting up Hot Corners has been moved in Mac OS X Lion as part of Mission Control, here’s how to set it up:
- Launch System Preferences and click on “Mission Control”
- Click on “Hot Corners…” in the lower left corner
- Set the screen corners you want to use to “Put Display to Sleep”
- Close out of System Preferences and test the Hot Corner by sliding your cursor into that screens corner
In the screenshot example, the lower right corner is set to put the display to sleep, while the lower left corner starts the screen saver. Sleeping the display is more akin to turning it off, and it’s not the same as putting the Mac to sleep.
If moving the cursor isn’t your preference, you can also setup a keyboard shortcut to lock the Mac screen. In both cases, if you have a password enabled for the lock or screensaver screen you will need to enter the login credentials again to regain access to the Mac OS X desktop.

I forgot these exist, good tip
I use the hot corners for dashboard, mission control, application windows, and launchpad.
It was the closest I could get to ‘gestures’ before gestures, and I can do it with my mouse. Which works great when i’m in OSX on the desktop where I have yet to buy a track-pad, but like one handed control.
In my opinion Active Screen Corners is the most annoying feature of Mac OS X.
It’s so annoying when you work as a system administrator at a company which has a few hundred Macs and everyone has set their own Active Screen Corners preferences.
When I want to click on the Apple logo on those Macs, I just move the cursor to the top left side of the screen, but on every Mac something else happens. Some people configures their Mac to open Dashboard, other people have it configured to open Mission Control, others use this corner to start the screen saver. It’s so annoying. I just want to click the Apple logo, but it’s impossible to predict what’s going to happen when moving the cursor to a corner of the screen.
I know, if Dashboard or Mission Control or a screen saver starts, it means I’ve moved the cursor too far to the corner, but I don’t use Active Screen Corners myself (why should I if I can use gestures?), so I’m used to just quickly moving my cursor to the cursor of the screen.
I’ve been using hot-corners since before gestures existed. As far back as Mac OS7. It all comes down to what helps the work flow of the person who has to use the computer. This also opens up gestures to perform other functions. But still, for those of us without touch-pads, or who use both, hot-corners makes more sense. And when I want the Menu, which is rare, i just move the cursor to the Apple; and the tangent of going to the corner accidentally is easily fixed by going back to the same corner.
Though I do know what you mean, I use them, and every time someone who doesn’t uses my computer normally tries to they end up someplace the don’t mean to be.
Personally I’m not a fan of hot corners either – I find them far too easy to trip accidentally. Anyway, I just wanted to add that the way I do this is through the SHIFT-CTRL-EJECT shortcut. Much easier!
[...] Corners are a great feature of Mac OS X that let you instantly enable things like the screen saver, sleep, the lock screen, LaunchPad, Dashboard, Mission Control, and new with Mountain Lion, Notification [...]
[...] popular approach is to use a hot corner for inducing sleep immediately, but that’s easier to accidentally trigger than a keyboard shortcut. Similarly, if you have [...]