rename many files...

for i in `ls -l | grep -i billund|grep -v flat|awk {'print $9'}`; do (mv $i `echo $i|sed -e "s/billund/ongar/g"`); done;

replace string 'billund' with 'ongar'
for i in `ls -l | grep -i ongar|grep -v flat|awk {'print $9'}`; do (cat $i |sed -e "s/billund/ongar/g" > $i.new);done

move 'new' files into place of 'old' files
for i in `ls -l *.new|awk {'print $9'}`; do (mv $i `echo $i|sed -e "s/.new//g"`);done;