I'm soooooo stoned...

Our cats have strange substance abuse habits. Mina, as we may have mentioned before, has a strange fixation on dryer sheets - licking them, nuzzling them, and occasionally trying to disembowel them. Riley, as we were reminded when we brought in tonight's groceries, treats celery like catnip. elalyr tore off a leaf for him and was rewarded with the spectacle of a tabby writhing on the kitchen floor, apparently stoned out of his gourd. Is this the cat equivalent of getting drunk on non-alcoholic beer?