Parallels today released an update for their OS X virtualization software that will allow Mac users to download, install, and run the Windows 10 Technical Preview as a virtual machine. Yes, Windows 10 on OS X (ten) through Parallels 10. It's a mouthful, and technically experimental support right now. But it's also another avenue for people to try out Microsoft's latest and greatest OS (itself in a not-quite-finished state) without having to resort to crazy things like partitioning.
The update to Parallels brings it to version 10.1.4, and is a free update for existing Parallels 10 users. If you have an installation of Parallels 8 or 9 it's a $49.99 upgrade, while new customers will have to fork over a hefty $79.99 for the privilege of running a virtual Windows 10 machine on their physical OS X machine. That said, it does give the Mac user much more flexibility in their choice of OS — they can concurrently run OS X and with Windows 10 (as well as older versions of Windows, Ubuntu, and more) in a window.
If you want to check it out, the update for Parallels is available now, or you can download it for a free two-week trial from the Parallels website.