Mega-CD



Known as Sega CD in the US, this was not just a CD drive for the Mega Drive: it added a faster CPU, new graphics and audio processors, and more RAM. All this power was mostly wasted on interactive video shovelware; nonetheless, this system had a good number of quality games.

Hint: as it was released long before CD burners became popular, it has no copy protection whatsoever (although the games are region-locked).