VBA (VisualBoyAdvance) for mac. It does the job, but I find that several games are unable to save. It gives an error that says "Cannot find backup save" or something weird like that. (The messages are in-game, not an actual error message from the Mac or the VBA emulator.) Games that I find that do this are FFTactic Advance and FF1&2 Advance and GoldenSun2. I have to remember to Freeze state my gameplay lol.