The Wien Pervert is a man who calls girls living in Wien (on their room phone) and famously whispers to them "Guess why I'm whispering". This is, of course, the most freaky thing that could ever happen. According to a Public Safety official, the Wien pervert has been sexually harassing girls for over a decade. It is theorized that he looks up girls on the Columbia website in order to get their room number.
Dealing with him
For most people this will not be a problem--simply disconnecting your room phone will prevent him from ever contacting you. If you need to use your room phone, usually just hanging up will suffice to quell his perverted efforts. Although he has been known to call back, these instances are rare. What you should not do is ask him exactly why he is whispering, because then he will divulge on an explicit explanation on what sexual things he wants to do to you.