The impending disaster in this embedded video is being orchestrated by something languishing with the name iTray, which is an iPad-controlled helicopter food tray thing a trendy London sushi establishment is using to ferry food to its customers. As a one-off stunt thing, but still.
The "flying waiter" is being used to promote a new range of rice burgers (?) the Yo! Sushi chain is now selling to people who are sufficiently engaged with its brand but not yet ready to take the full leap into eating raw fish. Lets hope it doesn't go out of control and decapitate any of those dreadful people, eh? [YouTube]