From http://www.boingboing.net/2010/12/18/magnetic-yellow-card.html

Someone’s made a chuckable “you’re driving like a tool” magnet for cyclists to affix to cars. Good idea or fanning the flames?

Some people (the ones that need glasses) will not be able to read/ see it.

(1) This seems to be a revival of something that came into a existence a few years ago.

(2) It’s still a really crap idea.

what about those stickers that were a right PITA to remove?

Can’t we just keep paint stripper in our water bottles and squirt them when they carve us up?

Always very satisfying when I (allegedly) did it as a student.