Genesis Plus is a fairly well tuned Genesis emulator for the mac, supports saved states, gzipped ROMs, and battery saves.

BIN format ROMs are supported, and Gzip compressed ROMs can be used transparently. The successor to the successful Sega Genesis, the Saturn has a dual-CPU architecture and eight processors. Two different video rendering engines are provided one for maximum speed, and one for accuracy. The Sega Saturn is a 32-bit fifth-generation home video game console developed by Sega and released on Novemin Japan, in North America, and Jin Europe. It supports full sound emulation, with accurate emulation of both the YM2612 FM chip and the SN76489 PSG. Generator is compatible with the majority of Genesis software. This is (was) a port of GenEm to PowerPC.

Yay! Easily the most advanced Genesis emulator for Mac. Besides being the first Genesis emulator ever to have interlace support for split-screen games, this is the first Genesis emulator for Macintosh to SUPPORT FM SOUND, which means you're actually going to hear some music. This is Dave's Genesis Emulator ported over to the Macintosh.

Fusion is a Sega SG1000, SC3000, SF7000, Master System, Game Gear, Genesis/Megadrive, SVP, Pico, SegaCD/MegaCD and 32X emulator for Win9x/ME/2000/XP/Vista/Win7, Mac OSX(Intel), and Linux.

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