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Step 1. Click the Print Screen key and paste the clipboard contents in MS Paint. Save the image as .bmp in any c: drive
Step 2. Select all icons on coworkers' workstation screen and move them to a new folder in c:
Step 3. Open the .bmp picture in Windows Picture Viewer, right click and choose "Set as Desktop Background"
Step 4. Walk towards the Office pantry to join your friend for coffee.
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And if you don't want this trick to be played on you, always Lock your Windows XP Workstation by pressing the Windows Key + L.
Original Idea: Tech Prank: Freeze Frame