If you have no idea what the Humble Bundle is, let's get you all caught up. The Humble Bundle is a collection of games that are sold together, and the user is the one that sets the price that she is willing to pay. That's right if you want 4 games and only want to pay a dollar, then that's all that you pay. Sounds like a recipe for disaster, but it's actually made quite a lot of money not only for the devs themselves, but charities too.
As you can see, it looks like Mac users might make up less than 25% of of the total contributors, but they tend to donate more per person.
So what games are up in this bundle?
For two weeks, the Humble Indie Bundle V will let purchasers pick price points for Psychonauts, Limbo, Superbrothers: Sword & Sworcery EP, and Amnesia: The Dark Descent. Anyone who pays more than the average price will receive another title to sweeten the pot: Humble Bundle veteran Bastion. Also, every game you unlock includes its soundtrack.Sounds like a great deal, and currently, if you donate more than $6.14 you get Bastion too. These games work with Steam, Mac, PC and Linux, so there's really no excuse not to get the games!
Source: The Verge