pass / no-pass bumper signs

Over the years I've seen many trucks that have signs on the rear bumper indicating that it's preferable to pass on the left and not a good idea to pass on the right. Often the indicators are simple, like...
<---PASS...................NO PASS--->
<---YES.............................NO--->
<---GOOD ........................EVIL--->
<---LIVE ...........................DIE--->

Sometimes they get much more creative, such as.......
<---ZOOM ...................KABOOM--->
<---YANKEES ...............RED SOX--->
<---BLONDE ...............BRUNETTE--->
<---ONLY THE GOOD....DIE YOUNG--->


Do these type of pass/nopass indicators have a name? I've been trying to find if there's a website that has more of these types of signs.

Does anyone have any links with more, or maybe share some of the more funny or clever ones you've come across?

Thanks
Etz

 

Those two additions are good.

But c'mon people, there's got to be more of them out there!

Cheers,
Etz