Street art, such as sculptures, murals, graffiti, poster art, is commonly displayed on buildings, walls, sidewalks – anywhere it can attract public attention.  This week Patti invites us to share images of street art whether it is scrawled messages all the way up to the most elaborate of commissioned work.  Even though Boston Massachusetts is full of beautiful and interesting murals and graffiti, I decided to feature four pieces of commissioned works of art and public statues.  The header shot of the Tortoise and Hare at Copley Square, was created as a tribute to all Boston marathon runners by Nancy Schon in May 1995. This first street exhibit more than…