There is Kega Fusion for the pc. A very nive emulatore that supports SG-1000, SG-3000, Master System, GameGear, Genesis/MegaDrive, SegaCD/MegaCd, 32X, and 32X CD. I tried it on a friends pc and works great but alas, I cant find one for mac.
Has any one installed XP on their intel macs? If xp runs well I may just try that.