smashing windows with the cover option. I mean they react to it with surprise and look at you. But they overall just seem to go "eh" and move on.
Funniest one I got was at Beecher's Hope. Saw Abigai wiping down the kitchen window. Went inside and smashed it in (which logically would send the glass at her. After the initial shock, she just continued wiping the (now non-existent) window.