yt is a community-developed high-performance analysis and visualization toolkit for astrophysical simulation data. This video by Matthew Turk gives an excellent introduction to it:
The yt webpage is, in my view, a model for the content of a collaborative software project – if you are releasing a community software home page, I recommend a look at the content and organization of yt’s page.
The front page contains a concise mission statement: “The yt project aims to produce an integrated science environment for collaboratively asking and answering astrophysical questions. To do so, it will encompass the creation of initial conditions, the execution of simulations, and the detailed exploration and visualization of the resultant data. It will also provide a standard framework based on physical quantities interoperability between codes…” and describes the three characteristics of the code: data driven, community driven free. The links off the home page tell you how to get the code and build it, provide examples and troubleshooting guides, and describe how to contribute.