The nih class offers support for grant applications to NIH, the National Institutes of Health, a US government agency. The example-* files provide a template for using nih.cls and submitting the biographical sketches the NIH wants. They (potentially) use denselists package, which just reduces list spacing; the package is distributed with the class, but is not part of the class proper. (The examples may be distributed without even the restrictions of the LaTeX licence.)