Features project on CodePlex:

Project Description
This is a project for SharePoint 2007 Features. Features add new functionality to a SharePoint 2007 farm, site collection, or site. This project will create Features to address deficiencies in SharePoint 2007 or add new capabilities. You should understand a little about Features before trying these out. The packages here use batch files or WSP files to install the Features. After installation, be sure to activate the Features to see them in SharePoint.

http://www.codeplex.com/features