If you have (or get) the GNU Aspell library, you can use Text::Aspell to locate words that would be considered typos according to the Aspell dictionary:

use strict;
use Text::Aspell;

my $suggest = ( @ARGV and $ARGV[0] eq '-s' ) ?  shift : '';

my $speller = Text::Aspell->new or die "dang it\n";

while (<>) {
    for my $word ( grep /^[a-z]+$/i, split ) {
        next if ( $speller->check( $word ));  # skip if word is in dic
+tionary
        print "misspelled word: $word\n";
        if ( $suggest ) {
            my @suggestions = $speller->suggest( $word );
            my $advice = ( @suggestions )
                ? join( " ", "Might be one of:", @suggestions )
                : "No idea what that should be.";
            print "  $advice\n\n";
        }
    }
}
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There's even a way to specify a word list of your own choice to serve as the "dictionary" -- there's some info about this in the Text::Aspell manual.