For me, guilty pleasure night is this:
A really hot bubble bath, with a cup of hot tea with lemon and any of my favorite books, followed by snuggling in bed with DH and 3 out of the 4 furbabies (Bia is too big to fit in the bed) and watching something cool on tv or dvd.
If DH is in school (which is almost over!!!) then my idea of guilty pleasure night is hanging out in front of the computer reading fanfic.