adding a date to the last of each file name

i have some files in my directory....wit names say aaa, bbb, ccc,,,,,
i want to make loop so that for each file name,,,,,,a sysdate should be appended in the end.........and the files should look like aaa_20100331

i knw date can be appended as `date +"%Y%m%d"`
but m nt able to make a loop. kindly help me

thanks in advance

day=`date +"%Y%m%d"`
for files in `ls`
do
mv ${files} ${files}_${day}
done

you can change the `ls` part to show only the files you need

thanx dat is working perfectly