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SO true on the dorm room door thing. The ONLY time it should be closed is when you are not in the room, when you are sleeping, when you are changing, and if you are naked with a girl =P. MAYBE when you are studying for a really important test and can't be interrupted. Otherwise, keep it open. People will stop by to chat, see what you are up to, etc. I am fairly introverted and am not a fan of clubs and such, and still met a TON of people, including many of my now closest friends, just by mingling in the dorms.

The other thing is, when someone's door is open, their room is fair game. Make it a habit to go out and visit people's rooms.. see what cool computer game they are playing, chat it up a bit.

You'll meet people in no time.. college rocks.
 
My college was only a couple of miles from my house so I didn't move, but I remember just sticking to the only person I knew there (friend from school). Heh. Good times though, met my girlfriend of 6 years on our first day there. Really good times :)
 
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