The Rohloff might not be that much heavier when compared to the complete package of traditional shifters, cassette, etc. Check the Thorn website
http://www.sjscycles.com/thornwebsite/raventour.html
and see the clever photo of their hub in a scale. Yes is is pricey but quite innovative. About a $1,000 I think compared to the $200 Nexus. Go with the Nexus 8 that has the red line around the hub, its the premium version which is about 10oz. lighter with improved needle bearings.

Dos anyone know where to get a Thorn in the US?

My Nexus 8 has been awsome on a Breezer Uptown 8. Not fast. Not light. Just great all-around.