But what is an Alternate File Stream?
An article I wrote at Brighthub explains what these are.
How can you find them?
AlternateStreamView is a small utility that allows you to scan your NTFS drive, and find all hidden alternate streams stored in the file system. After scanning and finding the alternate streams, you can extract these streams into the specified folder, delete unwanted streams, or save the streams list into text/html/csv/xml file…..AlternateStreamView – View/Copy/Delete NTFS Alternate Data Streams.