perl -ne '$|=1; foreach $_ (split //) {print; select(undef,undef,undef,0.01);}' [filenames...]

##</code><code>##

#!/usr/bin/perl -w
# slowprint.pl, by Weyfour WWWWolf (Urpo Lankinen)
# Use however you want, but keep my name here. No warranty.

use strict;

BEGIN {
  $|=1;
}

while(<>) {
   foreach $_ (split //) {
        print;
        select(undef,undef,undef,0.01);
   }
}