Street art (sometimes called graffiti art) is a very unique and interesting form of modern artistic expression. The vivid colors and neverending creativity of their artists have a tendency to impress both locals and tourists alike. Like most major metropolises Toronto boasts its own collection of graffiti art, including the aptly named "Graffiti Alley," which runs parallel to Queen street on the southern side. To check out the wall art for yourself, start at Queen and Spadina and head west, walking down every alley you pass. There is also a healthy amount of graffiti artt scattered a few blocks north…