I just thought I'd post a few examples of cool graffiti we've seen here and there while on vacation. Here's a massive spaceman several stories tall in the Turkish quarter in Berlin:
And here's another cool bit of graff covering a metal door of a quite industrial building in Berlin:
This fun graff can only be seen from the highest point atop Parc Guell in Barcelona, which means only an intrepid few who hike to the top of the mountain ever see it:
The park below the precipice from which this photo was taken contains several buildings and structures designed by the (astonishing, half-crazed) Antoni Gaudi, which is what most people are there to see.
Barcelona has the largest quantity of high-quality street art of any city I've ever visited. There are multiple books available for purchase featuring literally thousands of photos on the subject and there are full-blown graff murals throughout the narrow, winding streets and on every underpass I've seen. Last night (regrettably we didn't have the camera with us) we ran across about 8-9 excellent murals, all apparently done illegally (you can tell the commissioned stuff because the topic relates to the businesses) painted on the metal doors shop-owners pull down over their entrances when they close up at night. Without question, I've seen art in high-class museums on this trip that I didn't enjoy so much.