A while back I came across Tony's post about creating custom STSADM commands and I thought it would be cool to be able to see what files in a web had been unghosted. I followed Tony's instructions and added a simple recursive function to check the page customization status:

As it turns out, there are three different statuses a page/file can be in:

Uncustomized:    The page is cached and has not been customized

Customized:    The page was cached but has been customized

None:        The page was never cached

For this example I can get a list of unghosted (customized) files and display that back to the user:

You can download a copy of the class file here.