The command line is very powerful for things such as mass renaming of files. example rename a series of files from me*.txt to you*.txt or do a mass renaming of extentions.

I also use it to catalog cd contents such as dir d: > cd1.txt the you can concatenate all your files.

Endless ways to use it. Of course if I need to move a bunch of files the explorer would be faster.

The power of the command line is one reason I think that apple added the command line to their new OS