As I've outlined over the many years we've produced these Automator tips, this fine utility can be used in powerful ways to make your work easier. However, in the hands of the office prankster it can also be used as a useful tool on the first day of April.
The following workflows require that you have access to your target's Mac and user account. No one but a fool would leave their Mac open in such a way, but finding such fools is exactly what April Fools' Day is all about, right?
The devious desktop
Automator allows you to choose any image you like and use it as a desktop pattern. Feel free to click on the image below to expand it to its full size. Click on the image and then drag it to your desktop to save it. If that doesn't work, Control-click (or right-click) on the original image in this story and select Open Link In Window. Drag and click from there.
Plant that image in a not-entirely-obvious place on your victim's Mac. Launch Automator (in /Applications) and in the template chooser that appears, select Application and click Choose. In the Finder, drag this image file into the workflow area. This creates a Get Specified Finder Items action that points to the image.
Now select the Files & Folders library and from the Actions column next to it, drag the Set the Desktop Picture action into the workflow area. Save your workflow and in the sheet the appears choose Application from the File Format pop-up menu, give it an innocent-sounding name such as "Clock Sync," and save it to the same somewhat-hidden location you saved the image file.
Launch System Preferences, choose Users & Groups, click the Login Items tab, click the plus (+) button below, and navigate to the workflow you just created to add it. (No, you don't need to have the user's administrator's password to add a login item.) When the person who normally uses this Mac next restarts it, they'll find that their Mac sports a radically different look.
To undo what you've done: Remove your Clock Sync application from the account's login items. Control-click (right-click) on the desktop and choose Change Desktop Background from the contextual menu. Select the old desktop background.
The transforming Trash
You and I know that with Mac OS X, the Trash icon is now found in the Dock and not on the desktop. But if your friend is a Mac user from way back (or just not very observant), they may fall for this one.
Create another Application workflow. Select the Files & Folders library and drag the Rename Finder Items action into the workflow area. (When you see the warning, click Don't Add.) From the action's top pop-up menu choose Name Single Item. Configure the pop-up menu and text below to read PLEASE DON'T KILL ME!!! Save your workflow as an application and name it Trash.
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