At Dunkin’ Donuts, “Dunkin’ Dave”–that’s Dave Puner, 35–posts as many as 12 tweets a day during the workweek to 9,589 followers, or people who are signed up to receive his messages. His posts are laid-back, uncensored riffs on the weather, songs that contain coffee lyrics and thoughts about his own caffeine addiction. His easygoing Twitter tone is supposed to mirror the “average Joe” Dunkin’ Donuts seeks to attract.

“We talked a lot about what our voice should be,” says Margery Myers, the senior vice president of communications at the Canton, Mass., company. “Dave has a very dry sense of humor and he’s comfortable expressing himself online.”

San Francisco-based Twitter is a natural tool for some personalities, such as Shaquille O’Neal, and cult brands that want to broadcast their doings. For quirky and informal Jet Blue, the Twitter format is perfect for delivering product news. The airline, which uses Twitter to promote deals and suggest travel tips, has 154,663 followers.