I once saw a bumper sticker on some flash car (sorry, don't remember what it was - I'm a girly girl in that respect!) that said, "My other car is a Volkswagen Beetle." Wow. A custom-made bumper sticker...!
Fave bumper sticker I've heard about, but not seen:
Ginger Rogers did everything Fred Astaire did, but she did it backwards while wearing high heels
Fave t-shirt I saw in a catalogue once:
wysiwyg
And fave recently-acquired t-shirt:
YOU DON'T KNOW ME
Federal Witness Protection Program
Most appropriate bumper sticker, seen on a car that had slewed across the sidewalk and hit a telephone pole:
If you don't like the way I drive, stay off the sidewalk.
Bumper stickers I wish I had:
If you're rich, I'm single
and
So many men, so few who can afford me
(and surprisingly enough, they don't really reflect my attitude! but I just find them a hoot...anyway, I wouldn't put a bumper sticker on my baby - I like a pristine car. But I like reading them on other people's cars! Wonder who on earth first came up with the idea of the bumper sticker?)