If I have one complaint about the Bluetooth car kit I installed in my car a couple of years ago, it's that it can only pair with one phone at a time. Sure, you can pair it with four different phones – just not at the same time. If it's paired with your wife's phone and you're driving the car, you can end up in awkward yelling across the driver scenarios that just plain suck. That's why the new carkit from Uniden sounds interesting – it'll pair up with two phones at the same time.
It's a tiny little portable unit, and comes with text to speech caller ID announcements, voice dialling and 15 hours talk time. There's also your typical noise cancellation and a blue-backlit OLED screen. It'll retail for $120, although you should be able to find it for less online, if being able to talk handsfree on two different phones while driving is important to you.