I mean, something like these from Runter vom Gas:
http://i.auto-bild.de/ir_img/1/1/3/6/2/ ... 439231.jpg
http://www.dvr.de/bilder/presse912.jpg
http://www.dvr.de/download/autobahnplakat_kind.jpg
http://www.dvr.de/download2/p2947/2947_1.jpg
I always see tons of them along german roads. Have seen similar posters in map mods too, and they definitely improve the autobahn atmosphere in my opinion.
Unlike distance and navigation signs, I guess they're not that time costuming to add either. Say you make four or five different posters, you can just randomly add them "everywhere"? Hence, an easy way to improve the detail level
![Smile :)](./images/smilies/icon_e_smile.gif)