Back to the question of "cool things about perl6"- after showing some of the extended syntax and its expressiveness, put up a slide saying "it's still Perl".
Show that much of the basics still work: > my @x=('a' .. 'z'); @x[3,4]=qw(DeeDee Ramone); say @x.splice(2,4).join(',') c,DeeDee,Ramone,f the splice and join as methods instead of subs is different in p6 then p5 but should still look familiar. And if that is too harsh there's "use v5" so one can use the old syntax, if there's a want or need to. The real benefit/amazing thing about perl6's back-compatibility is the ability to still use the substantial mass of code libraries in cpan- use Catalyst; Huge plus there! It's good to show/remind people that their investment in perl is still valid when they pick up perl v6. That's one of the amazing things. IMHO, it is really cool that the perl6 specs mandate that older perl modules will work... just as I was happy that perl 5.0 let me use my old perl 4 packages, with single quotes instead of "::" and all... I'd also like to help "nip in the bud" a tendency to view perl v6 as a different language from perl v5. Along those lines, might be worth mentioning how perl 6 is already leaking into perl 5.10+, things such as "say", the smart-match operator "~~", and various cpan modules that implement perl v6 features like gather/take in perl v5.