Here's a pretty good deal from Amazon. Buy Bioshock for $50 and get The Darkness for free. "But the shipping," you say. "But the tax," you say. "I cannot afford such things," you say. "I'm saving for a new KitchenAid mixer to make game cakes," you say.
Amazon gives free shipping on orders over $25, and there's no tax in most states. For those interested, hit the link and scroll down to the "Best Value" option. That's where the hot savings are.