Tonight’s PSA: How to remove a bumper sticker.

This site has the full details, but the very short version is: WD-40 will shift that sucker for you most of the time. Well, that’s what WD-40 does.

If you’re a more eco-caring type, this site has eco-friendly suggestions. They probably won’t wreck your bumper too badly before you give up and try the WD-40.