Trippy paint job dude!!!

I keep seeing these cars with the paint job that one minute looks green and the next minute looks purple (as well as other colors).

How do they do that?

I’m sure it has something to do with polarization or reflectivity, but it’s been awile since I took Physics (that and I was tokin’ pretty hard back then).

This was discussed just 2 days ago, but I’ll admit I had some trouble finding it. http://boards.straightdope.com/sdmb/showthread.php?threadid=85389

Please direct any remaining questions on this subject to that thread, as I am closing this one.

bibliophage
moderator GQ