In Tasmania, widows are required to wear their dead husband's penis around their neck for a period of time after his death. A similar law is enforced in Gippsland, Australia. 

An ancient law in Indonesia prohibited men from masturbating. The punishment was decapitation. 

In Bhutan a younger brother is not allowed to lose his virginity before his older brother. Furthermore, a younger brother may not marry before his older brother. 

In Peru, men are not allowed to have sex with a female alpaca. 

In Uruguay, men cannot touch their wives during their menstrual period. If convicted of this crime, a man can be fine and publicly whipped 200 times or more. 

In Iran, married men can legally have homosexual sex with their wife's father, brother, or son. 

The owner of every hotel in Hastings, Nebraska is required to provide each guest with a clean and pressed nightshirt. No male and female—even if they are married—may sleep together in the nude. Nor may any sexual activity be undertaken except while the couple is attired in one of these plain white cotton nightshirts.

In Krakow, Poland, wives are allowed to beat or kill any woman who is sleeping with their husband. She can either beat the woman to death or just wound her unmercifully. However the only weapon she may use is a club. 

If a husband catches his wife in bed with another man in Uruguay, he is given several options on how to handle the situation under the law. One option is to kill the wife and her lover, no questions asked. The other option is to castrate the man with a knife and then slice off the nose from his wife. 

In Yemen, prostitution is illegal. Women convicted are publicly beheaded. 

Rapists in Nambia can choose either castration or 20 years of hard labor. 

In Communist China, anyone caught distributing pornography is sentenced to death. 

In Florida, having sexual relations with a porcupine is illegal.

Indiana and Wyoming both have laws against anyone's enticing, alluring, instigating, or helping a person under 21 to masturbate. This activity is known in legal circles as an act of "self pollution."

New Jersey law threatens men with a three-year sentence for "mutual masturbation." The law covers anyone "who, in private, is a party to an act of lewdness or sexual indecency with another."

Michigan law prescribes five years in prison for a man who engages "in acts of gross indecency, either in public or private." This includes mutual masturbation by two men or the simple act of solitary masturbation.

No one may have sex while riding in the sidecar of a motorcycle in Norfolk, Virginia, where an old ordinance outlaws anyone from doing so while cruising down a city street.

No man is allowed to make love to his wife with the smell of garlic, onions, or sardines on his breath in Alexandria, Minnesota. If his wife so requests, law mandates that he must brush his teeth.

Warn your hubby that after lovemaking in Ames, Iowa, he isn't allowed to take more than three gulps of beer while lying in bed with you—or holding you in his arms.

Bozeman, Montana, has a law that bans all sexual activity between members of the opposite sex in the front yard of a home after sundown—if they're nude.

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Gathered from a multitude of forwarded emails and anonymous spam, not to mention reader submitted. If you see something you can legitimately lay ownership to, let me know.