Rename Files and folder to lowercase Linux

gistfile1.txt

This is a good one liner command, specially when dealing with lots of files that you want to change its names from upper-case to lower-case.

for f in * ; do mv -v $f `echo $f | tr '[A-Z]' '[a-z]'`; done

That will work on all files in the current folder, if you want more specific files use this form

for f in `find . -name '*.rar'` ; do mv -v $f `echo $f | tr '[A-Z]' '[a-z]'`; done
This last case, will look for files with .rar extension, you can use find with all its options to improve your search.

Rename Files and folder to lowercase Linux