This week several articles hit the wire describing that US Customs is allowed to make you log on to your notebook and access and even copy the data on it.
This is basically not new as the police is allowed to screen your notebook if they have a court order or at least a reasonable suspicion. Time will prove how US Customs is handling this and how often this happens. It might well be that we have to re-think our data handling policies.
There is one story about this: http://www.iht.com/articles/2006/10/24/business/laptop.php