etiquette: http://www.rotozaza.co.uk/etiquette2.html Etiquette is a half-hour experience for two people in a public space. There is no-one watching - other people in the cafe or bar are not aware of it. You wear headphones which tell you what to say to each other, or to use one of the objects positioned to the side. There is a kind of magic involved - for it to work you just need to listen and respond accordingly. Best done with someone you know, someone to share this with.