Checked out this website today whilst looking at rooftop signs and billboards..  Really good site many posts relating to the work I am currently thinking about.  This post is really interesting in how it shows us the results of Sao Paulo's decision to stop all street advertising.  The before and after pictures really do show how the city came back to life once the signs were removed.  Old buildings reappeared and streets came back to life quite a dramatic change.  Local graphic artist and photographer documented the results where signage was left standing with no message.. Check out Tony de Marco and his photos.