...besides the obvious one that you're a safety menace to everyone around you if you're using your cell phone while driving -- no matter how careful you think you're being while you're talking (let alone text messaging). But now comes word that mobile phone chatters are also slowing down everyone's commute.
"New computer simulations show that chatty drivers — using regular cell phones or even hands-free devices — take longer to complete their trips because they drive more slowly on highways and pass sluggish drivers less frequently," LiveScience.com reports.
"Delays in traffic streams of very small amounts grow into massive numbers when you project it across a highway and across a nation," Peter Martin of the University of Utah's Traffic Lab told Reuters.
Earlier studies have "equated the risk of driving while talking on a cell phone with driving while drunk," Reuters notes.
Get off the phone when you're driving.