I'm saving the best till last: Sid Meier. The man. The legend.
Two of the greatest games ever to carry his name are available right now for just over $1 each. They're available for the next day and a half, roughly. And you should take advantage.
Good Old Games are selling a five pack bundle of classic Microprose games until, according to the time at the time of writing, 1am Sunday morning Sydney time. There are some games in there that absolutely won't be most people's cup of tea -- such as the Silent Service games -- but there are at least two titles that everyone with a PC, or a Macbook, should take the time to play.
Those are Sid Meier's Colonization and my personal favourite, one of the best Civilization-esque games ever produced: Sid Meier's Alpha Centauri.
You can purchase them right now for $1.19 each as part of GOG's Winter Bundle, although the entire pack -- which comes with Pirates! Gold Plus and Sid Meier's Covert Action, both good games in their own right -- is a measly $5.95.
It comes at a perfect time too, because getting Alpha Centauri for super cheap will help you avoid Civilization: Beyond Earth, which is sadly one of the most underwhelming titles Firaxis has produced to date.
Alpha Centauri was their first. It's still their best, although the XCOM reboot was very, very good indeed. (XCOM 2 is shaping up nicely too.)
Get this now. And Pirates! too, if you're after something a bit different.