Tapping out an e-mail on your Blackberry under the conference room table.

Resetting your ring tone to your favorite song or line from a movie.

Keeping your Bluetooth in your ear during a business lunch.

Think no one noticed those technological faux pas? You're wrong — many people see it as rude.

"They're so busted," said Linda S. Gravett, of Gravett & Associates, a human resource management consulting and training services firm in Anderson Township, Ohio.

During her training sessions, she asks managers and employees about their hot buttons. Sending e-mails or instant messages instead of taking notes on a laptop is mentioned every time, she said.

Mary L. Starvaggi, a Loveland business etiquette consultant who runs a business called The Etiquette Advantage, said wearing an iPod can be like "hanging a do-not-disturb sign on your desk."

She said iPods and the like are more acceptable in creative industries but warns against blasting the music or bass, singing or dancing.

And when someone stops by your desk to talk, taking only one earbud out is "almost like not giving complete eye contact when listening."

Under-the-table texters are about as subtle as study-hall note passers, the experts said. Multitasking is a weak excuse.

Gravett, the co-author of "Bridging the Generation Gap: How to Get Radio Babies, Boomers, Gen Xers and Gen Yers to Work Together and Get Results," said she has watched people text through a class, then stare blankly during a group session.

"They're not multitasking as well as they think they are," said Gravett, who advises companies to set up a code of conduct about iPods and text messaging. "They're not totally present."

Starvaggi said to remember your parents' advice: "Just because everyone's texting under the desk or the conference table doesn't make it right."

As for cell phones, keep the volume down as low as possible, and don't subject your co-workers to the first eight bars of "Dancing Queen" a dozen times a day.

"The ring tone should be professional if you want to be perceived as professional," said Starvaggi. Those rules apply whether you're an employee or a customer.

"You order your lunch, you get your food, you pay — the whole time you're on the cell phone," she said. "You never acknowledge the people there. To me, that is the epitome of rudeness."

The management at Habanero in Clifton, Ohio, agrees. About three years back, the restaurant posted a sign telling customers not to talk on their mobile phones when ordering, manager Paul Nordan said.

"We were getting a lot of complaints from workers," he said. "They felt offended by it."

Join our discussion: What are your pet peeves?