Boxer is a DOS game emulator for OS X, built around the powerful DOSBox — aims to make it easy and painless to play your DOS games. DOS game emulation lacks an equivalent to console ROM files, which contain a game’s data in a single file that’s easy to store, distribute and launch.
Boxer aims to address this with DOS Game Packages. These bundle a game’s files and configuration settings into a single tidy container, and can be created from an existing game folder just by renaming it. You (or anyone with Boxer) can then play the game just by clicking on the package.
More info: Boxer
You can also play with a cool tool called “Virtual ][” that lets you play the old Apple games, because it supports all graphics modes, lets you control the game paddles with a USB game pad or mouse and emulates the internal speaker. When you want to temporarily interrupt gameplay, Virtual ][ allows you to save the entire virtual machine, and continue later on from where you left off.
More info: Virtual ][