A bear is walking through the woods when he sees a rabbit hopping along the trail. A brief conversation ensues:

Bear: "Hello Mr. Rabbit"

Rabbit: "Hello Mr. Bear"

Bear: "Say, do you have a problem with poop sticking to your fur?"

Rabbit: "Why, no I don't"

So the bear wiped himself on the rabbit.

That's the "cleanest" one I know. Horrible pun intended...
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