Open source Sonic the Hedgehog for the browser.

Open Sonic is a free open-source game based on the "Sonic the Hedgehog" universe. It introduces a different style of gameplay called cooperative play, in which it's possible to control 3 characters simultaneously. Unlike most similar games, Open Sonic provides a greater level of interaction between the player and the levels. It's more than just a jump'n'run; the user must come up with some strategy in order to get through the levels.

• Open Sonic JS @ GitHub.

A Java-based Sega Mega Drive/Genesis emulator. And other systems too.

Initially created as a Sega Megadrive/Genesis emulator and then evolved to emulate the following systems: Sega Megadrive/32X, Sega Master System/Game Gear, Sega Sg-1000, Colecovision, MSX v1, NES