Delete

This prank will make your friends think that all of their files are being deleted and then at the end the file deletes itself so it is untraceable. 

@echo off 

echo do you want to delete all of your computer data? (y/n) 

pause >nul
echo Do not exit out of the screen or all computer data will be deleted. 
ping localhost -n 2 > nul 
echo Are you sure you want to delete all computer data? (y/n) 
pause >nul 
echo deleting all data... 
echo. 
echo. 
pause localhost -n 2 > nul 
dir /s 
echo. 
echo. 
ping localhost -n 2 > nul 
cls 
echo error.. error.. Not all data deleted, are you sure you wish to stop? (y/n) 
pause 
echo. 
echo. 
ping localhost -n 1 > nul 
cls 
dir /s 
echo. 
echo. 
ping localhost -n 2 >nul 
cls 
echo all data has been deleted.. 
pause 
del "c:delete.bat"

Save it as Delete.bat