Gamefly offers downloads of Sid Meier's Civilization V: Brave New World Expansion Pack for Windows or Mac for $7.49. Coupon code "GFDJAN25" cuts it to $5.62. That's tied with our mention from three days ago and $17 below the lowest total price we could find for a shipped copy of this expansion pack.

Note, this expansion pack requires the base game Sid Meier's Civilization V and a Steam account.