At the end if you wait out hte credits you will be able to roam the rooms. There is a cipher on the floor(to see it use you eagle vision). I can't decode it but i bet someone else can. It reads:

morymnors

enceolcht

nonbtlotc

tdeosatoa

pedsnlstf

lddvooete

eaieirint

hshkttker

t4aaanssa

another one reads:

a

drh

oodtm

whbitdo

e4s45inse

aroomrea4nr

ise4thidlmide

twihw4iea4dayhl

12212012