I've used Boot2Docker - it's "point, click and ship Docker hosting" for Windows or MacOS X and it bundles the open-source piece of VirtualBox to get that done. I haven't used it on a Mac but on Windows you download an installer and run it. It installs VirtualBox, Windows MSYS Git and the Boot2Docker Linux infrastructure.
You double-click on a desktop icon and it creates a VM for the Linux Docker host, fires it up connected to a VirtualBox host-only network and gives you a command line window in the VM where you can do "docker run" on anything from Docker Hub, or build your own images and containers.
My own personal testing is down a different path - I'm testing Atomic as a guest in the "native" Windows 8.1+ (Client) Hyper-V. I've hit a few bugs with Fedora, most notably
https://bugzilla.redhat.com/show_bug.cgi?id=1097772, but I have gotten Atomic to boot and talk to the command line - next step is to hook up networking and verify that containers can talk to, for example, a browser.