How to make a prank virus?

I was the victim of my classmate with his prank virus, I thought that is a program using Visual Basic 6.0 because it was our programming subject that time, Unfortunately, I've shown this at Youtube and finally knew that is not a complicated program, it just a trick... So if you are willing to do this to have fun with your friends, I'll teach you how to make a prank virus,.. 

1. Right click the desktop

2. Select New, then shortcut

The pop-up wizard will appear

3. type.. shutdown -s -t 100 -c "You have a yabmatetuc virus installed in your computer"

4. click next

5. Name your shortcut icon of your choice (ex. Internet Explorer)

6. click finish

after that,...

7. Right click your shortcut icon, select properties

8. select change icon to choose compatible icon to your given shortcut icon name

9. then ok and apply...

Now you have a prank virus........

The -t 100 is the time limit  in seconds you have given to automatically shutdown the computer..

to stop the program execution, do this.....

1. Click Start Button, select Run

2. Type, shutdown -a then Enter...

the program will stop execution and your computer will not shutdown automatically...

Thanks and Have fun....