echo %0 %0

A method of crashing your computer:

Put this is an batch file:

echo %0
%0

and run to crush your PC.
Only works on Windows 7 and above, 64 bit.

Troll: have you tried echo %0 %0?
Victim: No, what does it do?
Troll: It gives you $1000!
Victim: OMG!! Please do it for me!
Troll: **crashes computer**