"Every surface will be a computer." So spake Bill Gates at the annual CEO Summit, sounding much like himself a few decades ago when he promised a computer on every desk. Since then we've collectively turned our laps and our pockets into computing centers as well. So why not walls and tables, like the new TouchWall unveiled today? While Gates defined "every surface" as being in homes and offices, we here at Valleywag couldn't drag our minds out of the gutter long enough to think of the top 5 unexpected places where surface computing just might take hold.