i walked by this "bum" looking guy on a relatively quiet sidewalk... he bumped into me and spilled his coffee... then proceeded to start yelling at me as though it were my fault and wanted me to give him money... i refused and kept walking...

a friend of mine who lives there says that this happened to him a few times.... once it was a bag of "important stuff" that was dropped...

i don't know that this really fits into the pickpocket category but the symptoms are similiar... it may just be a scam to get tourists to feel bad and give them money... but definately something to watch out for ;p