DOSBox
From Applepedia
Miss playing your old favorite DOS games on your shiny new butan? DOSBox is undoubtedly the answer. DOSBox is a totally free, open source, multi-platform DOS emulator. Most games run at full speed, though there is a compatibly list you can check just in case.
It emulates an Intel x86 PC, complete with sound, graphics, mouse, and modem necessary for running many old DOS games.
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Pro Tips
- Running the OSX port can be tricky so be sure to read the manual.

