The blogosphere has recently been buzzing about what appears to be a growing practice of laptop searches when entering the United States. The NYT had a piece on this yesterday (At U.S. Borders, Laptops Have No Right to Privacy - New York Times) and Boing Boing is linking to it.
It's a long established soverign right to strictly regulate what comes into a country. Increasingly, information has value and is even regulated from both the export perspective and the import perspective. This appears to be a simple extension of customs officers having the right to go through your dirty clothes on your way back from vacation, but certainly has privacy effects.
More and more people keep intimate information on their laptops and crossing a border with one is akin to crossing the border with your personal archives. If they were in paper form, there's no doubt the customs folks would have the right to take a peek. But laptops also often contain information that is a cut above the routine. A lawyer's laptop is full of privileged material and a physician's laptop is full of confidential information. It doesn't sound like there are any protections built into the system to acknolwedge this and that's particularly troubling.