GreatBoxee is a project mainly written in Shell, it's free.
Great Boxee bits and bobs for developing Boxee apps
Download the build script (NAnt\package.build) and put in a folder inside your app in a folder called "Build".
Create 3 descriptor files in your app root, one for each location the app will exist or be deployed to. They must have these names (conventions!).
Full details here on how to use the packaging script http://www.greatboxee.com/index.php/2011/04/04/automate-your-app-packaging/
The Examples folder contains a full working example.
NB This is the NAnt version of the packaging script. There's also a Rake version in the Boxee Boilerplate
A photoshop template for creating app thumbnails. With a sash for each environment type (dev, beta etc) to distinguish between the environments the app is from.