It sounds like the opening line of a joke: French wife sues her ex-husband over his refusal to, uh, perform during their marriage. But the widely publicized lack-of-passion lawsuit raises the question: How much is marital sex worth?

The 51-year-old ex-husband was ordered to pay the equivalent of about $15,000 by a judge in Nice, southern France, for not getting busy in the bedroom with his 47-year-old spouse during the 21 years of their marriage, according to the British paper The Telegraph. The couple had divorced and then the wife sued for compensation for the long sex drought. However, suing a spouse, or an ex-spouse, for monetary damages is rare, and success rarer still. In 2004, a Spanish man tried it when his wife shut him out for five days and a judge tossed the case.

Even so, sex, or rather than absence of sex, finds its way into lawsuits all the time.

In the U.S. denial of sex is not usually spelled out in divorce codes, though “mental cruelty” fits the bill. Oklahoma has a provision for “gross neglect of duty.” In some states, plaintiffs can charge the defendant spouse with “impotence” and collect settlements. Other states specify that the impotence had to have been present before the marriage, a provision that harkens back to the days when people pretended not to have had sex before the wedding day.

More often, third parties are sued for causing “loss of consortium.” That does not always mean just sex -- it could mean hubby can no longer mow the lawn -- but generally that’s just a nice way of saying a spouse longer performs up to par, or at all.

In New York State, a wife sued a local town after her husband shattered his elbow tripping on a damaged sidewalk. She won $85,000 for loss of consortium, which sort of makes you wonder just how integral his elbow was to their “consortium.”

And, of course, there is the old “alienation of affection” lawsuit against a third party, such as a mistress. If a husband or wife stops having sex with the spouse because he or she is all worn out from lunchtime at the Motel 6, the spouse might collect loss of consortium damages from the paramour.

A big tobacco company was even sued for loss of consortium. In 1997, an Indiana woman named Norma Doerner sued Swisher International because her husband had smoked the company’s cigars and got tongue cancer. He eventually died of it and she sued. She lost the case, mainly because she’d divorced him six years earlier.

Exactly why the French fellow stopped having sex with his wife for over two decades remains unexplained -- he claimed he was too tired and had health problems, the paper reported. But the judge only valued his services at about $714 per year, so maybe his wife wasn't missing much.

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