One of my collegeas at Logica is working on a great tool for generating features in MOSS. As he states on his blog:
"The MOSS Feature Generator generates features out of existing functionalities on a MOSS 2007 site. This includes Site Columns, Content Types and ListTemplates (including schema.xml and forms). The tool will be expanded in two ways: a build tree will be created to make it possible to create dependant features in an organized way, and the number of supported features will be expanded."
I will keep an eye on his blog. Great stuff!!!
http://www.sharepointblogs.com/alfred/archive/2008/03/27/sneak-preview-moss-feature-generator-0-7.aspx
http://www.codeplex.com/mossfeaturegenerator