Majesco Entertainment is bringing Double Dragon Neon to Windows PCs via Steam during the first quarter of this year, offering a new co-op mode not offered in the console editions of the fighting game sequel. Here's a bit from a press release on Joystiq:

Billy and Jimmy Lee are back in Double Dragon: Neon, a reboot of the classic side-scrolling beat-em-up that is coming to Windows PC via Steam. To mark the occasion, developer Abstraction has gone back to the dojo and returned with an all-new online co-op mode for the true Double Dragon experience players have been waiting for. While taking down the Shadow Warriors and facing off with Skullmageddeon, co-op players can 'high-five' to share health, 'psych' up their comrades for special moves and revive their fallen partner. Keep an eye on your surroundings to discover life-restoring sodas, peruse the shop for items and find special mix tapes. The tapes can be stacked to pump up their effects, while playing two tapes at once creates a fusion of powers for devastating results!