From that spam telephone thread:

Tommy Cooper said that he rang someone up and said "Who's speaking, please?" A voice said to him "You are." :-)

Another of his: "I went to the ticket office at the station and said, can I have a return, please? The chap said, where to? I said, Here."

Another: "I rang up my local swimming baths. I said 'Is that the local swimming baths?' He said 'It depends where you're calling from."