I think the DVD Voice Activated Navigation System on the New Accords/TLs is the best one out there. Not only can you control the Nav system, but also the radio, a/c temp, etc. And plus I hear it's crackable to play normal DVDs on the screen.

 

I heard the voice activation ain't that great, like it's frustrating to get it to correctly recognize and interpret your voice. I've heard this in professional and owner reviews.