This might be good for you Mac / Linux gamers.
For today only (October 31st), you can get a copy of CrossOver for free.
CrossOver (a.k.a. CrossOver Office before version 6.0) is the collective name for two commercial and proprietary programs developed by CodeWeavers that allow many Windows-based applications to run on Linux and Mac OS X using a compatibility layer. The programs include CrossOver Mac and CrossOver Linux.
The programs are modified, proprietary versions of the public Wine source tree with various compatibility patches added, more user-friendly configuration tools, and commercial support. CodeWeavers employs several Wine developers and contributes code back to the free software/open-source software Wine project as per the GNU LGPL, although CrossOver is proprietary software.