[regomodo]

for I in {00..19};

do wget http://s3.amazonaws.com/bearwithclaws.baconfile.com/hackermo... ;

done

[6ren]

  wget http://s3.amazonaws.com/bearwithclaws.baconfile.com/hackermonthly-issue0{0..1}{0..9}.zip

Using "{0..1}{0..9}" instead of bash 4's zero-padding brace expansion.