TekSavvy, a Canadian ISP, has received its first ever demand from a copyright holder to identify its clients based on their IPs for alleged filesharing. (This is the same company that sued left right and center over The Hurt Locker).
Their response? They refused without a court order, informed all of the affected customers, and provided a FAQ about teh situation and Canadian copyright law.
TekSavvy - Copyright FAQs
Since the maximum penalty for file sharing (as of a week ago) under Canadian law is $5000, I suspect this copyright troll is going to be disappointed in the number of people who settle out of court.