How can I hack a wireless router? ?

I rent a few rooms in a house, and the owner (my landlord) just left on a three month trip but forgot to give me access to the wi-fi. This was part of our lease agreement. I called my landlord, but he forgot the password and he knows nothing about computers. Also, I cannot access the router directly because the door is locked.

So, I have no access to the Internet in my home, and my laptop mocks me when it says there is a wi-fi signal that I am legally allowed to use per my lease.

Essentially, I need suggestions on how I can obtain the use of my landlord's wi-fi when I cannot access the physical router AND my computer has no access to the internet. (I am typing this out on my dataphone.) In addition, the cable company won't help because I am not listed on the bill. Any help would be appreciated.