At some point in the life of any technology there comes a tipping point when that technology goes from something special to something expected. We’ve see this before with the lightbulb, indoor plumbing, and the telephone. Twenty years ago we didn’t see web addresses in commercials or know the email address of our news correspondents. Today we assume that every business has a web site, every person has an email address, and your boss looks at your facebook page. To that list you can add self-flushing toilets. They have become so common that people now expect them as witnessed by this sign over a uranal in Fort Worth. 
