I moved this page to rakudo wiki. A lot of people wanted to add stuff, but gists are not editable. A wiki is a more appropriate place for this kind of stuff. Rakudo wiki is possibly not the best place for it, but for now that will do.
Plus, GitHub gists totally suck when unicode characters are involved. There's also no preview option here. So I'm glad that it is being moved.
Recently Perl 6 got support for various unicode characters (½ ¹ ∞ × ÷, see this link for a full list), but I don't think that we are done. Here is a list of things to think about.