F.L over at World of Spectrum Forums has ported the ZX Spectrum version of Barbarian to the Sega Megadrive/Genesis! You can download the port (and other versions) over at http://barbarian.1987.free.fr. The rom works on a real Sega Genesis/Megadrive (ntsc or pal), and on emulators. (Kega Fusion works best)
Download: barbarianSPECTRUMmegadrive.zip
Website: http://barbarian.1987.free.fr
Forum Thread: http://www.worldofspectrum.org/forums/