I saw one that read "BUMPER STICKER". Wish I had bought it now.
I remember that one, a friend had that one on her car. I thought it was one of the best and funniest. The only one that might have been better was one that said "StickerBumper"
I keep a lookout for that if you return the favor for me --
My neighbor had a lovely sisal doormat that said GO AWAY.
I've been looking for one ever since. :-)