If you're anything like me, sometimes you need to find out what the ID of a SharePoint feature is and it can be something of a trial to locate the exact ID, especially if there's no handy SharePoint Server to remote onto and then go and search the FEATURES directory. So, a much easier way to get the ID of a feature is to use the Developer Toolbar (if you're using IE). Turn on the developer toolbar and select the Activate button of the feature you're interested in using the element selector. The button is enclosed in a DIV which has an ID attribute as follows:
As you can see from the image, the ID attribute of the DIV is a GUID, and this GUID is the Feature ID. Simple.