Germany's national railway says it spends $10 million a year cleaning up graffiti. Its proposed solution? Drones, which will hover around 500 feet in the air and use cameras and infra-red sensors to catch vandals spray-painting trains at night, the BBC reports. Each drone will cost around $77,600.
The plan is still in testing phase, but could prove controversial amongst Germans, who value privacy. Google Street View cameras caused a ruckus a few years back, and as many as 200,000 people asked for their houses to be blanked out on the service when Google was forced to offer an "opt-out" option. Deutsche Bahn says it will only operate the drones on its private land. (Read more drones stories.)