4 Mac Pranks for April Fools’ Day! (Part 2)

Back in 2012, I wrote an April Fools’ Day article about fun Mac pranks you could play on people. Well, heck, let’s do another one, you guys! I probably shouldn’t admit how much I enjoy pranking the folks I know and love, as that might make them love me a little less. If you too are willing to forego a little affection for a chuckle or two, let me be your guide. 

Flash the Screen

You’re probably familiar with the fact that the Mac will play an alert to warn you when, for example, an incorrect keyboard shortcut is pressed. There’s a setting hidden within System Preferences that’ll flash the screen white when that happens, too, which is handy for folks who can’t hear alert sounds but confusing as heck when you aren’t expecting it. All you need to do is visit System Preferences> Accessibility on the Mac you’d like to configure, click on “Audio,” and then turn on the checkbox:

You can also press the “Test Screen Flash” button to see what the prank will look like.

At this point, I’d suggest muting the machine’s sound, as that’ll make it more difficult for your target…I mean, your friend to figure out what’s going on. If the sound’s off, it’ll seem like his screen is flashing for no reason. Funny, right? RIGHT?!

Make an iOS Device Fill in Weird Stuff

Under Settings> General> Keyboard> Shortcuts, you can configure what text autofills when you type on an iOS device. As you can see below, I’ve set up a bunch of different shortcuts, including whole email responses that I have to use frequently. 

So when I type in “hth,” “Hope that helps!” fills in.

On that Settings screen, you can click the plus button to add a new shortcut, so if you’ve got a friend or family member who is crazy enough to trust you with her iPhone, you can add one in that’s, um, less than helpful.

On this trick especially, be careful that you don’t step over the line from “funny” to “horrible person,” OK? I don’t wanna be responsible for that.

Swapped Dock Icons

Changing someone’s Dock icons is really simple to do (and quite amusing!), but you’ll need to know the administrator password for the machine you’re setting it up on. To configure this prank, first open the Applications folder and find any program whose icon youd like to use. Click once to select the app, and press Command-I to open the Get Info window for it. Then find a second application to perform the mischief on. Obviously, you’ll wanna make sure that the program icon you’re swapping out is for an app that’s already in the Dock, and the more your target uses both of the applications you pick, the better.

Anyway, go ahead and perform the same steps as above on your second program. You’ll now have two Get Info windows open.

Go to the first window and click on the small application icon that appears at the top to select it.

Press Command-C to copy that icon, then click on the icon in the other Get Info window to select it instead. Press Command-V to paste the wrong icon in, and enter the administrator password when you’re asked to.

Oooo, that’s naughty.

To force the Dock icon to update with your evil changes, just quit and reopen the program in question.

Now you see iPhoto…

…but whoops! Now it looks like Mail!

One more thing: If you want to truly swap two Dock icons with each other, you can use Preview’s File> New from Clipboard command after you copy one of the app icons. That will place the item you copied into Preview so that you can go back and copy it again. After all, if you paste Mail’s icon onto iPhoto, you’ve gotta have a place to retrieve iPhoto’s icon to do the same thing to Mail. Clear as mud? Good.

When your target has been successfully freaked out and you’d like to undo your dirty work, pull up the Get Info windows for the ones you changed, click on that same small application icon, and press Delete to revert to the default. You’ll have to enter the administrator password again and relaunch the Dock icons, but after that, the machine will be back to normal. 

Make Crazy Stuff Happen with Folder Actions 

When you set up a folder action, any time your target adds a file to the folder you’ve picked, a selected action will take place. In this example, I’m going to use Automator to configure it so that putting an item into a folder makes the screen saver activate. That’ll confuse the bejeezus out of people.

There are tons of other Automator actions you could pick instead. “Launch Application” is another good one—it’ll make any program you choose open when a file gets added. If you’re curious, it might be worth messing around with Automator’s options to find one that hits your funny bone. I strongly advise against doing anything too evil, though. I mean, it may be a funny idea to make it so that any file added to your pal’s work folder gets sent right to the trash, but you know, I’d like to keep as many of my readers alive as possible. 

To get started, open Automator from your Applications folder, and when it asks you what file type you want, choose “Folder Action.”

Select “Utilities” from the left-hand list, and find “Start Screen Saver.” Drag that over to the rightmost pane.

As I’ve done in the above screenshot, you’ll then need to select which folder you want to apply this to with the “Folder Action receives files and folders added to” drop-down. After that, choose File> Save and give your nefarious little baby a name.

We’re almost done, I swear! Go find the folder you want to make a mockery of and right- or Control-click on it. From the contextual menu, pick “Folder Actions Setup.”

On the next screen, choose the new workflow you just created and click Attach.

You can verify that you’ve done things correctly on the following screen. Everything should be enabled, as below:

That’s it! From now on, every file dropped into that folder will invoke the machine’s screen saver. Since folder actions aren’t very well known, it’s pretty unlikely that the person you did this to will be able to figure out what’s happening, much less stop it from happening. Tee hee!

To undo this, right-click on the folder and select “Folder Actions Setup” again. Press Cancel when it asks you to attach a script, and then either turn off your workflow or delete it from that folder entirely using the minus button at the bottom.

Got any more fun tricks you like? Let me hear about them in the comments! I can always use extra ammunition in my house, people. And have a happy April Fools’ Day!