...not saying that black widows don't exist in Sweden because they do. ;D
Some months ago a newspaper reported that a man who imported an american car, got a little surprise. A black widow was apparantly included in the bargain

The spider had built a nest in the undercarriage and the man was so dead afraid so he told the paper that he will leave the spider alone until it dies from the cold climate...well guess what, the black widow was PREGNANT, meaning thousands of spiderlings in his garage.
Talk about being royally screwed ;D