WTF?

When I lived in the Twin Cities, I saw a bumpersticker on tons of cars, but I never knew what the hell it was. I saw them all over, on junky old cars, new sweet cars, but I could never figure out what the hell the sticker meant.
Just when I had convinced myself that I had made it up, yesterday I saw the sticker again!
Please oh please can someone tell me what this hell this thing means???
<--my crappy rendition