While in nethack, I’ve observed that:

• when I’m trying to chase a monster down, I often tap the keys more rapidly
• when I am about to strike at a monster I’ve been chasing, I hit the key extra hard
• when I am near a sleeping nymph I tap the keys lightly
• I am actually gravely concerned when I see a cockatrice, after way too many insta-deaths

Only while not in nethack do I observe just how much time I have spent on the game.