Best one I ever saw was only visible from close up and read:

"Get Any Closer, and you'll catch Aids!"
LOVElife Reviewed by LOVElife on . HAHA, Oh my some people are so dumb! I was just driving home and I saw a "Boycott France" bumper sticker just like the one pictured on an Infiniti SUV!!! LMFAO!! The driver was a woman in her mid 40's probably. My god I wish I would have had my camera to take a picture of that! I could have sent it into Top Gear! For all you that donâ??t know, like obviously that woman doesnâ??t... French auto maker Renault owns 44 percent of Nissan!!! LOL And of course Infiniti is just the luxury badge for Nissan. So she put a Boycott Rating: 5