Farabi You can try recent versions of Rakudo, Niecza, STD and Perlito 6 (four distinct implementations of Perl 6) using the fledgling (first appeared at the end of 2012) Farabi, an online “Modern Perl Editor”.
#perl6 If you just want to do some one liners, and would find it helpful to have folk seeing and commenting on what you enter and what results you get, you can try recent versions of Rakudo, Rakudo Star, Niecza, STD, and Pugs using evalbots on IRC channel #perl6 on freenode.net.

If you do want to install something, and are a Windows user, and would be happy with the Rakudo Star bundle (which adds docs, jnthn’s awesome debugger, the Panda module installer, some basic modules, etc. to the compiler), you can just grab the latest .MSI from the Rakudo downloads link.

If you want to use Niecza, or stay close to C# (which is Niecza’s underlying “systems” language), or prefer targeting CLR/.NET/mono (Niecza’s current bytecode target), you would want the latest from sorear’s Niecza github repo.