A more complex but very powerful set of tools that can be tapped for self help exist in the command line interface (cli) tools from the Darwin core of Mac OS X.  These are tools familiar to many users of UNIX-like systems such as linux, solaris, BSD, etc.  A simple tool like ls -al will list all of the files in a folder even those that might be hidden from view in the Finder and also show their dot extension.  This might help with problems like a document not opening in the correct application where ls -al would show no dot extension when one is needed.  For example a pdf file might be downloaded but no file type information associated with it and adding a .pdf on the end would make it open correctly.

A tool like rm could be used to remove a file that the Finder can not trash and a tool like asr (apple software restore) can be used to image a disk image onto an external hard disk for backup or recovery.