Amazon offers downloads of the 48-Game Sega Genesis Classic Game Pack for Windows
with a $5 credit to use on Amazon's bestselling games of 2013 in January.
. That's around 10 cents per game and the best price we could find for such a collection of SEGA classics. It includes Phantasy Star 1, 2, 3, and 4; Streets of Rage 1, 2, and 3; The Revenge of Shinobi; Wonder Boy in Monster World; and more.
Of note, you'll receive an email containing the promotion code for the credit. It must be redeemed in January.