1.63. A man is sitting in bed. He makes a phone call, saying nothing, and then goes to sleep. (SJ; from How Come?)
1.63 answer: He is in a hotel, and is unable to sleep because the man in the adjacent room is snoring. He calls the room next door (from his own room number he can easily figure out his neighbor's, and from the room number, the telephone number). The snorer wakes up, answers the phone. The first man hangs up without saying anything and goes to sleep before the snorer gets back to sleep and starts snoring again.
1.63 variant answer: (slight) It's a next-door neighbor in an apartment building who's snoring, rather than in a hotel. The caller thus knows his neighbor and the phone number.
1.63a. A man is sleeping in bed at 3 a.m. when the telephone rings. As the man lifts the receiver, the caller hangs up. (DW)
1.63a answer: Same situation, from the snoring man's point of view.