Lil' rat bastard.. :)
Considering the money I spend on bird food, nobody can say I don't like most of the visitors at my house. But there are a few "undesirables", regardless of how cute or furry they are.. But I tolerate them all, with very, very few exceptions.
Like this guy (gal?), for example - a red squirrel. I have one or more red squirrels in the loft above the main floor space in my garage (an old pig barn). And they make an incredible mess of everything - shredded towels, black walnut shells everywhere, etc. But it's a detached garage, and they haven't dug into either of my cars yet, so I deal with the mess they make. And once a year or so, they deal with a shop vac removing the mess they make, except for their nest, which I leave intact.
But these aggressive buggers do stretch my patience sometimes. Uprooting potted plants is my biggest complaint - and they don't care if you're looking. In fact, I think they like an audience. And my large bird-resistant and squirrel-proof suet feeder, well, isn't:
For now, I'm still tolerant :)