ViewNX2, although no top editor, is actually quite spiffy: reads all .nef files and picture styles, converts to major formats, allows a fast review, sorting and rating process, runs on older computers, does geotagging from .gpx files... and even performs some basic editing. Oh, and it's free, and easily dowloadable from Nikon.
Altough my workflow is Lightroom-centric, when travelling I bring along a small Asus netbook loaded with ViewNX2 just for backup and initial sorting and rating purposes.
http://egozarolho.blogspot.com 1. Good content, good aesthetics and good tecnique. On that order. 2. Light is more important than glass and pixels. 3. In the digital photography process, software is as important as gear.