The single won’t get you much more than a stiff nod and, these days, the fin is de rigueur. A tenner is a nice thought, but it’s also a message that you’re a Wal-Mart shopper, too cheap for the real deal. A twenty, placed in the right hand at the right moment, makes things happen. It gets you past the rope, beyond the door, into the secret files. The twenty hastens and chastens, beckons and tugs. The twenty, you see, is a verb. It’s all about action.