Here is a fun, funny, and easy way to annoy your friends and family members by (harmlessly) messing with their computers. This one is a simple batch file that makes a message box pop up that says anything you want. The trick: no matter how many times you click OK, the message will never go away! Have fun!
Step 1: The Batch File
1: Open notepad (under Start > All Programs > Accesories > Notepad
Copy and paste these lines into Notepad:
msg * Insert your message here
Be sure to delete "insert your message here" and replace it with your own message!