The local government in Papakura, New Zealand, has taken a hard-hitting and high-tech approach to road safety, by installing a billboard that bleeds when it rains.

The sign features the disturbing image of the face of a young boy. And it gushes with blood when touched by water. Nice.

It's all part of a campaign to warn reckless drivers of the dangers of driving in wet conditions. The country's heaviest death toll occurs during the heavy rains after every summer.

Unsurprisingly, the agency behind the terrifying billboards claims there hasn't been a single fatal accident in the area since they were put in place.

[Via Gizmodo]

In other weird news, scientists from Israel's Technion University have created a tiny robot that can crawl through your veins – and it uses neither an engine nor onboard controls. Uh-oh.

Instead, the 1mm-diametre bot is propelled forward by a magnetic field outside the body, allowing doctors to guide it at up to 9mm/second. Thanks to a set of tiny arms, it's able to grip onto vessel walls and can even withstand massive blood flow, the researchers claim.

Vein-crawling robot

It's hoped that the capillary-crawler, which was made using Micro-Electro-Mechanical Systems (MEMS) tech, will be able to treat arterial blockage and cancer.

More from the world of Weird Tech

Also this week: magnetic caps could soon be boosting the power of your brain to learn, and McDonalds is to install electric vehicle charging stations at its restaurants.

The idea is that you can recharge your electric vehicle while munching on a Big Mac. Be prepared to spend a good four hours at Maccy D's, mind – EV batteries are notoriously slow to charge.

How much would you fork out for an iPhone case? $200? That's how much the Factron folks are offering their latest rangefinder camera-style model for – for an additional cost it also comes with a range of interchangeable lenses.

iPhone rangefinder case

[Image courtesy of Engadget]

Meanwhile, the tale of the elusive invisibility cloak took another twist this week, with the discovery of a new concept that allows "an illusion to sit in place of the invisible object".

Scientists in Hong Kong have discovered a new way to bend light, making one object look like another one. While this could be useful for a range of activities - not least for necking a beer in the guise of water while at work - the concept has yet to be put into practice yet.

And finally…

Spanish police have foiled an attempted jailbreak, after catching wind of a plot to free a drug trafficker from an island prison - using an inflatable zeppelin.

Officials believe the 13-foot remote-controlled craft was going to deliver night goggles, climbing gear and camouflage paint to the inmate, who planned to scale the prison walls and escape in a waiting vehicle. The crazy plot was busted when authorities intercepted the zeppelin when it arrived from an Italian town.

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