Washington, D.C., Atlanta, and New York have the largest populations of mobile users addicted to wireless e-mail, online surveys conducted by AOL last month revealed.

Whether they're in the bathroom, driving, on vacation, or even in church, people in the United States are using mobile devices to constantly check their e-mail. E-mail use on mobile devices has nearly doubled since 2004, and 59% of those with mobile devices check e-mail every time it arrives in their in-boxes, according to AOL's surveys, conducted in partnership with Opinion Research.

The surveys polled more than 4,000 respondents, ages 13 and older, in 20 cities across the country.

Forty-three percent of respondents said they keep their mobile devices nearby when they're sleeping to listen for incoming mail. With such a large number of the population getting broken sleep, it's no surprise that 15% of respondents described themselves as "addicted to e-mail," with many planning their vacations in places where they'll be able to access it. Eighty-three percent admit to checking their e-mail on vacation, the survey found.

Fifty-nine percent of people said they check e-mail in bed, 53% in the bathroom, 37% while they drive, and 12% admitted to checking e-mail in church.

"As the survey data shows, portable devices -- like e-mail itself -- are becoming more prevalent and easier to use. Because you can access e-mail services like AOL from virtually anywhere and on almost any wireless device, it is easier to stay connected to work, home, family, and friends through e-mail -- and instant messaging as well -- than any other form of communication," said Regina Lewis, AOL online consumer adviser, in a statement.

The survey found that mobile users in Washington, D.C., are most addicted to wireless e-mail, with 82% of Washingtonians having multiple e-mail accounts. The second-most-addicted city is Atlanta, followed by New York; San Francisco; Houston; Los Angeles; Seattle; Orlando, Fla.; Denver; and Miami.