Data leakage

Panda Security "recently surveyed 10,470 small and midsize companies -- those having up to 1,000 computers -- in 20 countries. Roughly half said that their organization had been infected by malware at least once in the previous year, and in the United States, 27% said the origin was a USB device."

Some firms routinely block the USB ports in their corporate owned PC's, some by inserting epoxy glue into them.

Seems they are onto something.

Here's more on the survey.