Sex sells—but sometimes better than others

Julia Wheeler | Photodisc | Getty Images

I figure the headline got your attention. After all, sex sells.

Which is why I'm talking about sex on a business website.

Contrary to popular belief, however, sex doesn't automatically sell well. Part of its success depends on the economy.

For example, The Economist reports that British prostitutes are having to cut prices as business slumps due to tough times.

"The days of being able to make a full-time living out of prostitution are long gone." Long gone? You're talking about the oldest profession here. I would wager this is a temporary blip. In any case, the article claims many prostitutes are taking up legitimate side jobs to supplement their income. (I thought it used to be the other way around, women with "normal" jobs turned tricks on the side to make extra cash.)

(Read more: Americans and the News: Lots of Faking)

Selling sex well also depends on clever marketing, but woe to those who besmirch an American icon. Los Angeles-based porn producer Caballero Video has reached a settlement with Ben & Jerry's. The adult film makers have agreed to stop selling videos with titles and packaging mimicking the ice cream giant. The Los Angeles Times reports there will be no more "Ben & Cherry's" videos, including those with titles like "Boston Cream Thigh."

At the same time, sex may be under threat from something even more powerful—staying connected, er, virtually. A survey done by Harris Interactive for tech company Jumio found that one in ten people have used their smartphones during sex. It's one in five for people ages 18 to 24. At first I thought this meant that they were using the phones to, you know, record the event for posterity. No. While that may account for some of the usage, it appears people are on their phones for a variety of reasons and just can't put them down for a single minute. Or ten. Don't you know the NSA is listening? There's got to be a marketing campaign in here somewhere. "Think Different. Put the phone down. We'll still be here."

(Read more: Instagram vs. Vine: 9 Seconds Matters)

Finally, people who use smartphones during intimacy probably don't have much intimacy. Which means they probably don't have kids. Tomorrow, August 1, is their day. Actually, it's a day for anyone who feels left out on Mother's Day and Father's Day. It's International Childfree Day, described as "a day of celebration worldwide for those couples who have faced criticism, ridicule, and rejection because they chose to be Childless by Choice."

Not childless by choice. Childless by Choice. It appears this is a holiday that Hallmark has so far failed to capitalize on. Mistake! However, for those of you looking for the right greeting card, I found a few here. "You will never know the joy of parenthood," says one card which shows a man hitting himself in the head with a hammer. "This might give you some idea of what you're missing."

—By CNBC's Jane Wells. Follow her on Twitter: @janewells.