- During reconstruction of the I-35 bridge over the Mississippi River in Minneapolis, lines and lanes were re-drawn on several other major roads to accommodate the extra traffic. After the bridge was finished, some of the re-drawn lines worked so well, they have remained.
- On winter roads covered with ice (or black ice), it's not possible to see the lane dividers.
What if we could have the lane markings always "on top", and easily changed to accommodate rush hour, presidential motorcades, HOV lanes, and so on?
Someone else has a similar idea to create your own bike lane: http://blog.wired.com/cars/2009/02/lightlanes-lase.html
I don't know how legal that is, but I love the idea.
*Reminds me of an infamous grade-school prank. This may be an old wive's tale, but someone told me it happened to them:
Prankster: Hello, is Mr. Wall there?
(you know mostly where this is going, but stay with me here...)
Victim: Um, no, I think you have the wrong number.
Prankster: What about Mrs. Wall?
Victim: No, you must have the wrong number. There are no Walls here.
Prankster: Then how do you keep your roof up? Haha!
Victim: WE HAVE ROPES FROM THE MOON. Haha!