Cyclist uses GPS tracking app to turn Baltimore into a drawing board [Yahoo]

You too can use your city as a virtual Etch A Sketch!
Personal GPS devices are one of the most useful inventions in recent memory, and while they are a godsend for finding your way through a maze of city streets, they can also apparently be used for artistic purposes as well. Michael Wallace — who goes by the Twitter handle @WallyGPX — has been using the streets in southeast Baltimore to draw impressive designs for years now, but his latest work is perhaps his most impressive yet.