In large company environments they use a central directory systems to authenticate users against when users login onto a Linux/Unix or Windows box. Most likely the central directory service will be based on LDAP or Active Directory (of Microsoft). On the Unix boxes there is then a client install that communicates with this central directory service. It is mainly in such environments that adhocr is an useful and powerful tool.
This tool runs perfectly on HP-UX and Linux. You could say it is a tiny ansible (without the configuration management piece).
See our adhocr project page at github
On T-Dose 2012 conference we presented this small open source project adhocr and you can watch the presentation giving an introduction and explaining the usage of adhcor.