CodeWeavers' CrossOver lets you run Windows apps on a Mac without installing Windows, and only for Cyber Monday, it's available for up to 70% off.
CrossOver makes Windows apps appear to simply be Mac ones and work without you having to install Windows and a Windows emulator — or pay for licences for those.
Plus it's constantly being updated, most recently bringing EA and DirectX 12 game support to the Mac.
There are two versions of the app, CrossOver+ and CrossOver Life. They're both the full version with no limitations, but CrossOver+ is an annual subscription while CrossOver Life is a single, one-time purchase.
Normally, CrossOver+ costs $74 for the year, but for one day only, that is slashed to $22.20 for a 70% savings. The saving also applies to future annual renewals, so this is a true bargain.
To buy CrossOver+, use the code BADASS70 at checkout on the official site.
For CrossOver Life, the discount is 23%, which takes it down from the regular $494, to just $380.38. To buy, use the code BADASS23 at checkout.
Note that this sale is solely for one day. Also, there are no refunds for copies of CrossOver+ and CrossOver Life bought through this sale.