vaseline
> A man doing market research knocked on a door and was greeted by a redhead with three small children running around at her feet.
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> He said, "I'm doing some research for Vaseline. Have you ever used the product?"
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> She said, "Yes. My husband and I use it all the time."
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> "And if you don't mind me asking, what do you use it for?"
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> "We use it for sex."
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> The researcher was a little taken aback.
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> He said, "Usually people lie to me and say that they use it on a child's bicycle chain or to help with a gate hinge. But, in fact, I know that most people do use it for sex. I admire you for your honesty. Since you've been frank so far, can you tell me exactly how you use it for sex?"
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> The redhead said, "I don't mind telling you at all. My husband and I put it on the door knob and it keeps the kids out."