Cassy sounds a lot like my Emmett, who did the same thing to my vertical blinds the very first week at my house! Took down the whole rod and scared me to death...and it took two more days to get the rod back up! But I think it must have scared him too, because he's never tried it again! That was 2 and a half years ago, and he's calmed down a lot since then. He still has his "psycho" moments when he runs around the house at top speed, but that usually means he wants to play. I agree, it's one of the loveable things cats do. And I guess we all have our spray bottles!