Yeah Richard, while i do not condone graffiti in places where it clearly amounts to vandalism, no one can deny that there is some considerable skill involved. If your interested there is a site:

http//www.graffitti.org/

There are many more, but on here there are some amazing murals in amongst just the kids tagging to mark their territory. I had to do an assignment on graffitti as part of my Art & Design course, and it was one of the more interesting subjects ive had to research.

Sled