Problem:

Is it possible to easily change the case of all files in a directory without renaming each one?

Resolution:

Yes.

The following script will  convert all file names from UPPERCASE to lowercase, preserving the file contents in their original case:

# Script to change file names from UPPERCASE to lowercase.

# Leaves the file contents unchanged!

#

for file in 'ls'

do

    mv $file 'echo $file | tr '[A-Z]' '[a-z]''

done

Changing the order of '[A-Z]' '[a-z]' to '[a-z]' '[A-Z]' in the above script will convert all lowercase filenames in a directory to UPPERCASE.