You can also build parrot and try out Rakudo. Afaict it's supposed to work both under cygwin and "native" windows (I know that jonathan mostly develops under windows, so it must work somehow ;-).

I personally believe I'll wait to see if somebody distributes ready made parrot builds complete of Rakudo...

Of course also ikegami's suggestion is not that bad - apart that I would be playing with an old pugs anyway: if it weren't for the issue being discussed here, I would have no need to have more than one perl on this very pc, and I somehow prefer to, but -I have to admit- for no logical reason and so it wouldn't be a problem either.

If you don't want to build anything at all, and only test small snippets, you can also use your favourite IRC client, connect to irc.freenode.org, and /msg the bot p6eval

At some point IIRC a machine with public access on request was being provided by some kind soul, too, to make experiments. (I was on p6l back then and it was announced there.) Is it still up and running?