Pay what you want for The Humble Introversion Bundle with Uplink, Darwinia, DEFCON and Multiwinia. Pay more than the average to get Aquaria and Crayon Physics Deluxe as well. Steam codes are included.
Meanwhile, Indie Royale's Really Big Bundle is available for preorder at $3.99. The games aren't yet public, but the title is stated to be a hint so I'm guessing Really Big Sky will be included. Desura sponsors Indie Royale so expect codes for their service. (I have not seen Desura codes for Humble this time around. Battle lines!)