rename -n "s#([A-Z])#\L\$1#g" *

#!/bin/sh
find `test -n $1 && echo $1 || echo "./"` -type f | while read f;
do
    dname=`dirname "$f"`
    fname=`basename "$f"`
    nname=`echo "$fname"|tr "[:upper:]" "[:lower:]"`
    mv "${dname}/${fname}" "${dname}/${nname}" 2>/dev/null && echo "${dname}/${fname} -> ${dname}/${nname}"
done