The latest Humble Weekly Sale is from Prison Architect developer Introversion. No, Prison Architect isn't in it - but buy in early to get a discount on the popular alpha.
Instead, the pack includes Introversion's award-winning back catalogue - Uplink, Darwinia, Multiwinia: Survival of the Flattest and DEFCON.
All are available DRM-free or via Steam for Linux, Mac and PC, Windows, Mac, and Linux; Uplink is also available on Android.
The bundle also includes source code for all games, and a couple of PC tech demos - Voxel Tech Demo and City Generator Tech Demo. Finally, you'll get access to Introversion Story, an interview with the founders.
Now for the bonus: if you pay more than $20 for the bundle in the first 24 hours, you'll get alpha access to Prison Architect and a full copy upon release. After the first 24 hours this price will increase to $25.
As ever, you choose how much you pay and how the money is divided between developer, organisers and charities. To date, the Humble Bundle scheme has raised over $13.4 million for charity.