OK, here's the gory details. Consider a 3x3 grid of shuffled letters; the goal is to generate all words, 4-9 letters long, each containing the centre letter. Proper nouns are not allowed, and neither are plurals ending in "s" (I can't do much about that, but at least I print a warning).

I gobble up all words fitting the criteria from as many free dictionaries as I can find (Chambers is supposed to be used, but it ain't available nor is it free). Each word is letter-sorted (the slowest part of the operation) and hashed; the value is a reference to an anonymous array of its anagrams as they're found. Still with me? I then dig out all permutations of those letters (8P(3..8) plus the centre letter), sort them and print them.

Some (revised) code snippets; avert thine eyes if BSD-style formatting offends thee:

$Data::Dumper::Terse = 1; # Briefer - looks nice (no silly $VARnnn)
...
print "\n### words ###\n", Dumper(%words)
    if ($Dbits & $D_WORDS);
...
if ($stats_required)
{
    ...
    if ($Dbits & $D_LENGTHS)
    {
        local $Data::Dumper::Indent = 0;
        local $Data::Dumper::Pad = ' ';
        print "\n### lengths ###\n", Dumper(@lengths), "\n";
    }
    ...
}
[download]

Hope that's clear.

In the unlikely event of being bored, I'll think about something like:

$Data::Dumper::Push(Indent Pad) # Save these
...
$Data::Dumper::Pop() # Restore everything
[download]

but "local" is just as good.

-- Dave