I've signed up for the 1 year adventure package in Afghanistan. I wanted to minimize the weight for camera gear to compensate for all the "other" heavy weight gear. I packed my D700, 28mm f/2.8, 35mm f/2.8, 60mm f/2.8 (in case I want to do some macro photos), 50mm f/1.8, 70-300mm and an SB-900. However, when travelling around I've defaulted with a 50mm and 35 or 28mm for most of my uses, depending on what I expect to encounter. The 28, 35 and 50mm lenses are quite light.
My secret weapon is a P7100 that fits into my pocket for portability.
However, I've found that the focus speed of the P7100 has let me down a couple of time. I must disclose that some of my conditions are a bit extreme...focusing through thick bullet proof glass in a moving vehicle is tough for sharp images. But, the D700 does extremely well.
Here's a sample of what I could capture through the thick glass with the 35mm.
Though not from a D700...here's an example of a lucky P7100 image through the thick glass moving quickly through town...