italians
(this one has a bit of background, basically our italian flatmate continually puts rubbish in the recycling and paper, glass etc in the bin. she does it to be a pain in the arse because she's deeply insecure for many resons, but the effect is it pisses me off and makes extra work for those of us who actually put the recycling out for collection etc, this is no reflection on italians in general but she is italian and so i think of them. most italians i have met have been incredibly genial and sensible however)