A fishing town in Ísafjörður, Iceland is experimenting with a way to get drivers to pay attention to the road. What they've come up with is this optical illusion:
Artist Jenny McCracken did something similar in New Zealand:
As did the New Delhi Municipal Council in India:
And there's this dastardly one in Vancouver:
It's an eye-catching idea, but do you reckon these are effective after a driver has seen them more than a few times? I figure it'd like watching a 3D movie, where after a while you're no longer conscious of the effect.