Salesman: Anything I can help you with, sir?
Philip: No, I'm just browsing. Actually, I'm supposed to be shopping for a Halloween costume. Oh, what's this? Oh, it's one of those things for finding your lost keys?
Salesman: Yes, but this one is totally new. Are you constantly misplacing your keys? Just touch the button on the locator unit, and the keyring emits a gentle beep tone to alert you to the whereabouts.
Philip: Well, that's nice, but what's new about that?
Salesman: Well, suppose you misplace your primary locator unit. Just use the equally handsome secondary unit and listen for the primary unit's own distinctive warbling.
Philip: That's a great idea.