Bashscripts.org

#!/bin/bash
mkdir penny;cd penny
for month in `seq -f "%02g" 1 12`;do
for day in `seq -f "%02g" 1 31`
do wget http://www.penny-arcade.com/images/2006/2006${month}${day}.jpg; done; done;
for i in *.jpg;do type=`eval file $i | awk '{ print $2, $3, $4 }'` ; correct_type="JPEG image data,"
if [ "$type" != "$correct_type" ];then rm -f $i;fi;done
exit 0