[draegtun]

I believe the original plan was that you could run perl5 & perl6 together like so...

    use v6;
    .say for 1..10;
  
    {
      use v5;
      say for 1..10;
    }

    # back to perl6

That might (still) be a pipedream however one reality which is working right now is that you can run some perl5 modules from within Rakudo (Perl6 on Parrot):

    use v6;
    use CGI:from<perl5>;

    my $q = CGI.new;
    print $q.header,
        $q.start_html('Hello World'),
        $q.h1('Hello World'),
        $q.end_html;

ref: http://news.ycombinator.com/item?id=2188433