You might find info in this snippet, this script and this more descriptive node useful.

My personal contribution is:

:map \# ^[I#!/usr/bin/perl -w^Muse strict;^M
[download]

update
I have been using Vim with embedded Perl for a while.
I don't think I am exploiting all the possibilities, but it is really helpful to have perl regular expressions at your disposal, so you don't have to think about the differences between the two RegEx dialects. Once you are used to Perl's syntax, capturing parentheses in Vim  \(.*\) look painfully unfamiliar.
I often use Perl's sort to manipulate my lines of text.

A nice feature is that you can test one or more lines of code, while you are writing them. Here is just one example:

# line 10 of your code
$a = sqrt(64);
[download]

If you want to see the result of that assignment (provided that your internal CPU can't calculate it :) this command

:10perldo s/$/$_/ee
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will append the result at the end of the line.
I mapped this command, referring to the current line.

:map _ee ^[:.,.perldo s/$/$_/ee^M
[download]

I am sure that there is a lot more than these few tricks. Having Perl embedded in your editor can trigger your imagination!

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