I had a concept like that before,too.  Have wireless free (which is what attracts a lot of people) and then sell coffee by the carafe, not by the cup, to those who plan on staying awhile, or who want to share a carafe (kind of like how some places sell pitchers of soda or beer).

I don't like a lot of the "big" coffee houses.  I prefer regular coffee from Tim Hortons, or the privately owned coffee houses for the "fancy" coffee mixes.  Of course, I make most of my coffee at home (hard to find Jamaican Blue Mountain served anywhere).  If you price out really expensive coffee down to the cup, nothing compares to making it yourself.