The US government shutdown is bad news for furloughed workers, but when it comes to video games, it's apparently a convenient excuse for an impromptu sale! GOG is currently holding what it calls the "Shutdown Promo," and has slashed prices on a bunch of great games. The pack includes a total of seven games, three of which are Mac compatible, and all of which are currently half price.
Among the Mac-flavored content is Theme Hospital, Alpha Centauri and (comically) the Redneck Rampage collection. If you happen to have a Windows machine (or a fancy Boot Camp installation) you can take advantage of the price cuts on Tropico Reloaded, The Guild: Gold Edition, Capitalism Plus and Capitalism 2.
If you happen to be one of the unfortunate furloughed government employees, you can email GOG with a photo of you holding your temporary lay-off notice and receive the entire collection for free.