Where do you live that people are sporting those bumper stickers? I need to get out more.
We had an "Evolve!" fish on our car until the adhesive started to wear out, but until then, we were the only ones we ever saw with one. Occasionally had grateful high school biology teachers walking over in parking lots to start conversations with us.
One of my faves was: "Custer died for your sins."
A bit outdated, but still funny: "Frodo Failed, Bush Has The Ring"
Some I'd like to see:
"US Foreign Policy: We'll Bomb That Bridge When We Come To It"
"When you see a rainbow, god is having gay sex"
"Eve was framed"
"Ask Your Doctor If Medical Advice From A Television Commercial Is Right For You"
"Reaganomics - The Biggest Ponzi Scheme Of All Time"