At work we have been doing alot of development around Software Subscriptions, and how to represent them to a machine as a collection of Entitlements (what a machine is entitled to have or do). It is a FOSS project which we have been working on it for a while, but have finally hung out an offical shingle. You can checkout the website at candlepinproject.org. The name is based on a place up near our offices in Westford. It is called the Bowladrome. The folks came up with the idea while bowling.
Tech wise, it is a pretty interesting project. Java Stateless App Server using Guice. It exposes a REST API provided by RESTEasy. It has Rails 3.0 front end, and some linux clients which are written in Python. All we are missing is Erlang and we would be all set.
Come on bye, check it out. The project is open and is being actively developed. If you work in and around software subscriptions we would be interested in your opinions.