paperlined.org
+evil > USB_jacking
document updated 9 years ago, on Jan 14, 2013
Documented incidents of USB sticks being used to target high-security organizations, by dropping them in a parking lot that employees use. USB sticks are one of the few ways to attack an air-gapped network.

Other instances that this attack vector is actually used in the real world:

Rumors about US federal agencies using cement to ensure that USB ports won't be used: