In Boing Boing today,

Xeni Jardin linked to an article in the IHT: Laptops, please: US law permits search, seizure at the border. On my way home from a recent trip from the US, I had this experience at Canadian customs. I was flagged by the guy and later he made a cursory look-see in my bag, he was most interested in the contents of my laptop. He was pretty chatty and said that one of their main missions at Canadian customs now was porn (along with guns and large sums of cash), which presumably was what he was checking on my machine.