How can I safely attach my bumper sticker?

I want to attach a bumper stick to the exterior of my car without using the normal adhesive stuff on the back of it for fear I'll never get it off. What do I do?|||I've even seen some people go as far as using scotch tape and putting it on the inside of the rear window.|||stick it on a window. no paint fade, easy removal.|||stick it on a window, the adhesive is lots easier to get off of glass than paint. and you wont have to worry as much about rust