This may alienate 3 or 4 of my 6 regular readers, but there are few things I dislike as much as a driver pulling a idiotic maneuver while on their cellphone. If people could drive reasonably while talking on phones, I'd have no problem with it. But they don't. So I do.
Read the studies. You're not a good driver when you're on the phone. And hands-free doesn't really improve your concentration. If you think you're a good enough multi-tasker to get away with it... you're freakin' fooling yourself! And you're a danger to the rest of us!
Note: I recognize the difference between a brief "Hello? Yeah, I'm on my way. 'k, bye." type conversation and the longer, chatty-kathy sort, and I have much less issue with the former. But one problem I see is that people aren't good at being short and getting off the phone.
I was recently nearly hit in the crosswalk while crossing on green because a woman who was busy in phone conversation that was apparently more pressing than watching where the F#@% she was driving. I'm fairly certain she never even saw me. No last second shock of realization, no attempt to steer around me as I leaped backward out of her path. Hopefully she got her stuff taken care of, because it was obviously very important. As important as she was.