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On sidewalks, in restaurants and in movie theaters, the sound of ringing is incessant.

In today's technology-reliant culture, it seems impossible to escape the annoyances of cell phones -- and the rudeness of their owners.

Some officials have become so fed up with loud mobile-phone rings and conversations that they've contemplated banning the use of cells in some venues.

But a few innovative companies are trying to encourage cell-phone courtesy in other ways.

A recent study found a decrease in the number of Americans who will use their phones in public places like movie theaters, but many mobile phone users remain surprisingly inconsiderate.

"To my big surprise 28 percent of Americans say that they still find it acceptable to use cell phones in a restaurant," said Delly Tamer, president and CEO of LetsTalk, the company that conducted the survey. "Someone somewhere has to make some rules."

To try to curb this kind of behavior, the Boston and San Francisco-based IDEO, the same firm that invented the computer mouse and the toothpaste squeeze tube, has come up with several cell-phone models that would deter people from having bothersome mobile chats in public. One of them shocks the caller if he or she talks too loudly.

"It's kind of like having your mother in the room reminding you," said IDEO General Manager Tom Kelley.

Thus far, laws designed to curb cell phone use have mostly been met with static – though one piece of legislation involving cell-phone safety was successful in getting through. In the interest of reducing phone-related highway accidents, New York passed a law last year that prohibits their use while driving. The move has prompted other states to consider similar bills.

But such laws don't prevent less risky situations of public cell phone calls, such as angering the people near you. That's where the etiquette rules and IDEO's concepts for "social mobiles" come in.

Besides the electric shock, another deterrent would allow callers in crowded or quiet public places to react to the person on the other end by pressing a button instead of giving a verbal answer. Different buttons produce different sounds depending on the response. A downside is the limited number of possible programmed responses.

A third, more fanciful, IDEO concept is a phone resembling a trumpet that users have to "play" to make a call. The embarrassment factor would be enough to deter people from phoning in public – but the disadvantage is trying to get cell-phone users to buy such a contraption in the first place.

All the models are still on the drawing board.

So, until the standards of etiquette are completed and circulated, cell phone users would be wise to heed these simple rules: Turn off the phone in restaurants, movie theaters, museums, libraries, churches and other public places where calls might be disruptive; speak quietly; and keep conversations short.

And if you are tempted to gab loudly or reveal intimate details during a public cell phone call, remember: The person you're talking to isn't the only one who can hear you. Everyone else around is getting an earful, too.

Fox News' Catherine Donaldson-Evans contributed to this report.