This is a weird statistic:

Some of the largest and medium-sized U.S. airports report close to 637,000 laptops lost each year, according to the Ponemon Institute survey released Monday. Laptops are most commonly lost at security checkpoints, according to the survey.

Close to 10,278 laptops are reported lost every week at 36 of the largest U.S. airports, and 65 percent of those laptops are not reclaimed, the survey said. Around 2,000 laptops are recorded lost at the medium-sized airports, and 69 percent are not reclaimed.

Travelers seem to lack confidence that they will recover lost laptops. About 77 percent of people surveyed said they had no hope of recovering a lost laptop at the airport, with 16 percent saying they wouldn't do anything if they lost their laptop during business travel. About 53 percent said that laptops contain confidential company information, with 65 percent taking no steps to protect the information.

I don't know how to generalize that to a total number of lost laptops in the U.S.; let's call it 750,000. At $1,000 per laptop -- a very conservative estimate -- that's $750 million in lost laptops annually. Most are lost at security checkpoints, and I'm sure the numbers went up considerably since those checkpoints got more annoying after 9/11.

There aren't a lot of real numbers about the costs of increased airport security. We pay in time, in anxiety, in inconvenience. But we also pay in goods. TSA employees steal out of suitcases. And opportunists steal hundreds of millions of dollars of laptops annually.
Source: Schneier on Security