CrossOver is a commercial compatibility layer by CodeWeavers, based on the Wine project, which aims to run popular Windows software on Unix-based operating systems. CodeWeavers released the first beta of CrossOver for Chrome OS three years ago, and now it's finally ready for the masses.
CrossOver 20 was released today as the first version that officially supports Chrome OS. It comes configured to run thousands of popular Windows applications, including World of Warcraft, Steam, Quicken, GOG Galaxy, Microsoft Office, and others. Unlike the Parallels-based VM that Google is working on, CrossOver translates Windows API calls as needed, rather than emulating the entire operating system.
The Chrome OS version now runs on top of the Linux container, instead of running as an Android application like earlier betas did. CodeWeavers said in a blog post, "We feel that providing CrossOver using this route provides a superior user experience." However, this does mean that older Chromebooks without support for Linux apps won't be able to use the newer version.
CrossOver is paid software with three packages available. You can buy the current version for $39.95, and a Pro version with free software upgrades for a year (plus discounts on future releases) and additional customer support is available for $59.95. Finally, if you think you'll use CrossOver until the heat death of the universe, a lifetime support option is available for $499.95.