Here's a problem that has vexed women of the North for eons: When bitter cold strikes, one can always don snowpants over trousers, but what if you want to wear a skirt? A Swedish entrepreneur has met the challenge with an insulated, zip-on overskirt. The cheapest model sells for $100 and it is taking Alaska by storm. Teachers wear them for playground duty. Even guys like them. Former Olympic skier Adam Verrier wears his when he volunteers at ski races. "I've worn a lot crazier things," he claims. "It's not like it's thong underwear."