Here are a few pointers to free software that pertain to the NIPS collection.

DjVu plug-in for Windows and Mac and DjVuLibre plug-in/viewer and command-line tools for Unix (with source code), to view and print the articles from your web browser.
NOTE: The Unix/Linux versions include compression and decomporession utilities, as well as a standalone viewer called "djview".

DjVuLibre: Open source implementation of DjVu with viewers, compressors, decompressors and utilities for various Unix platforms.

Any 2 DjVu conversion server: A free conversion server that allows you to upload documents in just about nay non-proprietary format and have them converted to DjVu and OCRed.

DjVu.org: Links to more downloads.