Chicago's transportation department has announced that they're going to try an interesting experiment to try to get people to slow down on a notoriously hazardous curve. They're going to use an optical illusion:
The yellow warning signs mounted along the road in recent years telling drivers to take the curve at 25 m.p.h. have had little or no effect. So the city has decided to try something new. In a few weeks, dozens of new pavement stripes will be laid down. At first they’ll be 16-feet apart, but as drivers get closer to the curve, the stripes will only be eight feet apart. "They provide an optical illusion that vehicles are actually speeding up and that causes motorists to slow down, which is of course, the intended effect that we’re trying to have at that location," said Steele.
Unfortunately there's no video of what this optical illusion effect looks like (the new stripes haven't been painted yet), but when I read this I immediately thought that if you combined the speeding optical illusion with randomly moving yellow lines, you could really mess with people's minds.