In the future, a liquid matrix of nano devices will coat our eyes, providing the ultimate in 3D heads-up displays.  In a time when over-population and global economic stagnation provides little material wealth for most, people buy virtual overlays that map to the physical realities of their environments. You might wake with your bedroom seemingly a Tahitian thatch hut on stilts over crystal blue waters, your shower a tropical waterfall.  Businesses and public places provide common 'surrounds.'  People present themselves to others wearing the virtual fashions they've purchased.

So, it's not surprising that hackers will find a way to crack such public views and replace them their own environments for the world to see.  Such graffiti will be, as its present form is today, illegal.

These two have stamped their view of a dojo over the platform area of a monorail station, while wearing coordinated virtual costumes.  This is what a police detective, who stumbles upon the scene on his way to work, would see:

-- Mark