Nikon D800E Voigtlander90 mm F3.5 SL II APO-Lanthar
I think I'm probably going to have to try very hard to resist buying all the Nikon fit Voigtlander SL II lenses. The 28mm f/2.8, though not available yet, is tiny and 180g. There is also a 75mm f/1.8 announced. I can't say often enough how beautifully made these are. They are incidentally made in the same factory as Zeiss lenses, as Cosina make these for Carl Zeiss in Japan. Zeiss lenses are more expensive but from my experience no better either optically, mechanically or in their quality of manufacture.
Voigtlander is pretty much my favourite lens brand. Since taking over the name Hirofumi Kobayashi, the CEO of Cosina and Leica enthusiast, his staff and engineers have done a great job. Their m-mount lenses, these SLR lenses and now the two fast m4/3 primes are all examples of the best photographic traditions.
I know its easy to say and not so easy to do, but if you get the chance do try to have a look at these lenses. I know not many people sell them, and in the UK as far as I'm aware only Ffordes in Scotland and Robert White in Dorset ever have them in stock. However if you're like me and you value high quality, well made primes and you have no problem using manual focus, then you'll probably like these. The bonus of course is that because there is no AF motor they are very small and light, though still have that wonderful metallic feel. Putting one of them on any of my CSC's always makes the camera feel a lot classier, I feel. Plus they make my D800 and D800E a lot more managable.