If your nascent attempts at street art are more this:
...then budding Banksy wannabes might find a new smart spray can in development interesting. The robotic spray can is capable of letting anyone, regardless of their artistic expertise, create large scale murals based upon existing images.
The robotic can is synced up with a PC, which tracks the "artists" movements using a pair of webcams and two QR codes above and below the paint cylinder. All an urban artist would have to do is then wave their arm in front of where they'd like the image to be replicated, and the computer would time squirts to hit the surface accordingly. For images using colour, it's simply a case of swapping out the can when prompted to by the computer.
As you can see from the video above, it's not yet a highly accurate procedure, but there's definitely a strong representation of the original images coming out, with little effort from the person holding the can. Scale up the pictures to the size of a building, and stray drips and splodges would be less obvious to a passer by. For now, the tech is limited to flat surfaces, but further development could let the images be created on more topographically complex canvases too. [Phys.org]