You can use unix command tr.
For example:

for upper_name in `ls -1`
do
   lower_name=`echo $upper_name | tr 'A-Z' 'a-z'`
   mv $upper_name $lower_name
done



On Fri, 27 Oct 2006, Igor Kresnik wrote:

> Date: Fri, 27 Oct 2006 11:13:05 +0200
> From: Igor Kresnik <[log in to unmask]>
> To: [log in to unmask]
> Subject: change files
> 
> Hello
> My name its Igor. i hawe lot files with large letters. how I can change this 
> files to little letters?
> Regards;
> Igor
>