A man-eating squirrel. No, really.
Personally, I think the squirril's main advantage is surprise. Nobody expects to be attacked by a squirril, after all. But, once forewarned, I'm predicting that it will be no more than a day before said squirril is punted across the street.
Yes, I'm laughing, but only a little. My eyebrows are up, but I also feel sorry for the people who will have to take rabies shots, now.