Riddle: A man is found dead while holding a gun. Next to him was a cassette tape, which had recorded something. When played, this message was played: "I don't want to live anymore" and then there was a gunshot, and the tape ended. The police knew it was a murder. How?
Answer: Because to play the cassette tape, it has to be re-winded, and since there was a gunshot, the man was dead at the end of the recording, and couldn't rewind the tape!