It has five wheels, though often think four, You cannot use it without that one more, You can put things in it, you can strap things on top, You can't find it in the market, but you can still go shop. What is it?
Whoever makes it, tells it not. Whoever takes it, knows it not. Whoever knows it, wants it not. What is it?
What is white, black, and red all over?
A skunk with a diaper rash! A zebra with a sunburn! A panda eating berries! Or a newspaper, whatever.