You can chop characters out like mad if you embrace the map EXPR, LIST syntax, instead of map BLOCK LIST. See, then:

map{$0{$_}++}split//,$_=<>;
@0=map{[$_,$0{$_},$_]}keys%0;
[download]

become two PRECIOUS characters shorter:

map$0{$_}++,split//,$_=<>;
@0=map[$_,$0{$_},$_],keys%0;
[download]

japhy -- Perl and Regex Hacker