Definitely the Parrot handsfree kit. I've got an MKi9200
I can plug anything into it that holds digital music or just talk talk talk. The voice recognition system is really good too and very accurate and if you say a person's name it will even ask you whether you want to call their home or cellphone. The noise cancellation is very effective so the person you are talking to hears no echo like you get with those "clip on to your sun visor" kits.
Installation was a breeze. It just plugs in between your existing radio and the wiring harness of the vehicle. The unit is controlled via a wireless remote so can be stuck anywhere you like in the cab via a sticky pad. Simple but effective.
Well worth the price tag and it's one of the safest ways to talk on the move (no wires dangling down or things stuck in your ear)
Go get one!