And you thought driving while texting was bad. Online market research firm Crowd Science released a report on the habits of Twitter users, and the line item that's drawing the most attention is this: more than one in 10 users copped to using Twitter while driving over the last 30 days. And nearly a third of users have done it at some point in the past.

(Small solace: checking one's account while driving is more than twice as popular as composing tweets while behind the wheel. Compare that to only 5 percent of other social media users who access their accounts while driving.)

There's also the expected: Nearly 60 percent of users have tweeted at work, 17 percent from a restroom (only 17 percent?), 31 percent from a restaurant and eight percent from a movie theater or live performance (although there seems to be somebody in every movie; perhaps it's the same person over and over).

Then again, 17 percent of Twitter users said they tweet out of peer pressure. Still more than a quarter of Twitter users tweet daily.

(Image from Crowd Science report.)