Yeah, it's kind of a big deal. The latest Humble Bundle contains a bunch of Sid Meier games, including Civilization III and IV, two Ace Patrol titles, and Railroads. Those who pay more than the average will also get Civ V with several extra map packs and Pirates.
As usual, some of the games' soundtracks are included, the games can be added to your Steam account, and many of them are unlockable on the Mac, as well.
A portion of the proceeds goes to charity, so you'd be cold-hearted not to partake, right?