MacVision-8 is the original port of Marcel DeKogel's Vision-8 Emulator, a CHIP-8 emulator to the Apple Macintosh Classic. Funny story behind this one; I did the entire port on a PC, never testing it on an actual Apple Macintosh until after it was released.
I let someone else take over the project after the initial release; he did an initial OSX port, but abandoned it. Source is available for anyone who wishes to contribute further changes to it.