This is interesting—

thedailybeast.com

As the leaked GOP PowerPoint prompts outrage, its scare tactics are field-tested on America’s highways. John Avlon—author of Wingnuts: How the Lunatic Fringe Is Hijacking America, available from Beast Books—on the grassroots campaign to poison the president.

Click Below to View America’s Most Virulent Political Billboards

Second link should take you straight to the slideshow; or you can find it at the article linked above.
Some of these I’d seen here, but not all. Yeesh.