Most of those don't mean anything special to Perl. They are just variables. But punctuation variables are nice for obfuscation because they are immune to use strict.

You can also have variables named "{", you just can't access them as simply: ${"{"}, @{"{"}, %{"{"} (and that doesn't work under use strict).

You are exploring the corners of the parser, not of Perl's variables.

%! is special (see Errno). @+ and @- were added to Perl recently (regex related). @_ should be familiar. (:

        - tye (but my friends call me "Tye")