Ah, sonic the Hedgehog.  The game that established the Genesis as a figure in gaming, the character that became a pop culture icon (at least in the gaming world, but it went a little further), was able to stand right beside Mario, and lest I forget, gave Nintendo the first taste of competition.  I had a Genesis, but I sold it, but after playing it on the great Sega Genesis collection on my PSP, the old days returned.  This game was a classic in so many ways.