Kevin Good thought there was an 80 percent chance he could successfully deliver his brother's wedding rings with a drone.

"The other 20 percent is that it could go crashing into the bride's mother's face," the Bethesda, Maryland, filmmaker told his brother. His brother was okay with the odds, despite the risk to his mother-in-law's makeup, and signed off.

A few weeks ago, sitting in the back row at the ceremony near San Francisco, Good steered the tiny drone to the altar, delivering the payload in front of 100 or so astonished guests. His brother grabbed the rings, then watched as Good buzzed the drone off into the blue sky.