1. When you feel your pulse on the right side of your chest, sort of close to your arm, so it feels like you've got two hearts.
2. When you stumble upon feeling sort of supernaturally omniscient (only not supernaturally). Once, I was riding the train on the upper level and we stopped at a station, and two people were stood chatting on the platform for a moment before saying good-bye and turning and walking away from each other in opposite directions, at which point the train started moving again so that I first saw the woman's face, looking quite smitten, and then we passed her up and I saw her friend's face from the opposite way, also looking smitten. I felt like god.